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| * | | | | | | | | | | | x86/hpet: Introduce struct hpet_base and struct hpet_channelThomas Gleixner2019-06-281-34/+48
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Introduce new data structures to replace the ad hoc collection of separate variables and pointers. Replace the boot configuration store and restore as a first step. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> Cc: Ashok Raj <ashok.raj@intel.com> Cc: Andi Kleen <andi.kleen@intel.com> Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com> Cc: Stephane Eranian <eranian@google.com> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Link: https://lkml.kernel.org/r/20190623132435.728456320@linutronix.de
| * | | | | | | | | | | | x86/hpet: Coding style cleanupIngo Molnar2019-06-281-17/+26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> Cc: Ashok Raj <ashok.raj@intel.com> Cc: Andi Kleen <andi.kleen@intel.com> Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com> Cc: Stephane Eranian <eranian@google.com> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Link: https://lkml.kernel.org/r/20190623132435.637420368@linutronix.de
| * | | | | | | | | | | | x86/hpet: Clean up commentsIngo Molnar2019-06-281-18/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> Cc: Ashok Raj <ashok.raj@intel.com> Cc: Andi Kleen <andi.kleen@intel.com> Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com> Cc: Stephane Eranian <eranian@google.com> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Link: https://lkml.kernel.org/r/20190623132435.545653922@linutronix.de
| * | | | | | | | | | | | x86/hpet: Make naming consistentIngo Molnar2019-06-281-10/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Use 'evt' for clockevents pointers and capitalize HPET in comments. Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> Cc: Ashok Raj <ashok.raj@intel.com> Cc: Andi Kleen <andi.kleen@intel.com> Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com> Cc: Stephane Eranian <eranian@google.com> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Link: https://lkml.kernel.org/r/20190623132435.454138339@linutronix.de
| * | | | | | | | | | | | x86/hpet: Remove not required includesIngo Molnar2019-06-281-11/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> Cc: Ashok Raj <ashok.raj@intel.com> Cc: Andi Kleen <andi.kleen@intel.com> Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com> Cc: Stephane Eranian <eranian@google.com> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Link: https://lkml.kernel.org/r/20190623132435.348089155@linutronix.de
| * | | | | | | | | | | | x86/hpet: Decapitalize and rename EVT_TO_HPET_DEVThomas Gleixner2019-06-281-17/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It's a function not a macro and the upcoming changes use channel for the individual hpet timer units to allow a step by step refactoring approach. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> Cc: Ashok Raj <ashok.raj@intel.com> Cc: Andi Kleen <andi.kleen@intel.com> Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com> Cc: Stephane Eranian <eranian@google.com> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Link: https://lkml.kernel.org/r/20190623132435.241032433@linutronix.de
| * | | | | | | | | | | | x86/hpet: Simplify counter validationThomas Gleixner2019-06-281-6/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is no point to loop for 200k TSC cycles to check afterwards whether the HPET counter is working. Read the counter inside of the loop and break out when the counter value changed. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> Cc: Ashok Raj <ashok.raj@intel.com> Cc: Andi Kleen <andi.kleen@intel.com> Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com> Cc: Stephane Eranian <eranian@google.com> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Link: https://lkml.kernel.org/r/20190623132435.149535103@linutronix.de
| * | | | | | | | | | | | x86/hpet: Separate counter check out of clocksource register codeThomas Gleixner2019-06-281-34/+31
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The init code checks whether the HPET counter works late in the init function when the clocksource is registered. That should happen right with the other sanity checks. Split it into a separate validation function and move it to the other sanity checks. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> Cc: Ashok Raj <ashok.raj@intel.com> Cc: Andi Kleen <andi.kleen@intel.com> Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com> Cc: Stephane Eranian <eranian@google.com> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Link: https://lkml.kernel.org/r/20190623132435.058540608@linutronix.de
| * | | | | | | | | | | | x86/hpet: Shuffle code around for readability sakeThomas Gleixner2019-06-281-40/+41
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It doesn't make sense to have init functions in the middle of other code. Aside of that, further changes in that area create horrible diffs if the code stays where it is. No functional change Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> Cc: Ashok Raj <ashok.raj@intel.com> Cc: Andi Kleen <andi.kleen@intel.com> Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com> Cc: Stephane Eranian <eranian@google.com> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Link: https://lkml.kernel.org/r/20190623132434.951733064@linutronix.de
| * | | | | | | | | | | | x86/hpet: Move static and global variables to one placeThomas Gleixner2019-06-281-28/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Having static and global variables sprinkled all over the code is just annoying to read. Move them all to the top of the file. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> Cc: Ashok Raj <ashok.raj@intel.com> Cc: Andi Kleen <andi.kleen@intel.com> Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com> Cc: Stephane Eranian <eranian@google.com> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Link: https://lkml.kernel.org/r/20190623132434.860549134@linutronix.de
| * | | | | | | | | | | | x86/hpet: Sanitize stub functionsThomas Gleixner2019-06-281-9/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Mark them inline and remove the pointless 'return;' statement. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> Cc: Ashok Raj <ashok.raj@intel.com> Cc: Andi Kleen <andi.kleen@intel.com> Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com> Cc: Stephane Eranian <eranian@google.com> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Link: https://lkml.kernel.org/r/20190623132434.754768274@linutronix.de
| * | | | | | | | | | | | x86/hpet: Mark init functions __initThomas Gleixner2019-06-281-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | They are only called from init code. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> Cc: Ashok Raj <ashok.raj@intel.com> Cc: Andi Kleen <andi.kleen@intel.com> Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com> Cc: Stephane Eranian <eranian@google.com> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Link: https://lkml.kernel.org/r/20190623132434.645357869@linutronix.de
| * | | | | | | | | | | | x86/hpet: Remove the unused hpet_msi_read() functionThomas Gleixner2019-06-281-7/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | No users. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> Cc: Ashok Raj <ashok.raj@intel.com> Cc: Andi Kleen <andi.kleen@intel.com> Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com> Cc: Stephane Eranian <eranian@google.com> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Link: https://lkml.kernel.org/r/20190623132434.553729327@linutronix.de
| * | | | | | | | | | | | x86/hpet: Remove unused parameter from hpet_next_event()Thomas Gleixner2019-06-281-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The clockevent device pointer is not used in this function. While at it, rename the misnamed 'timer' parameter to 'channel', which makes it clear what this parameter means. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> Cc: Ashok Raj <ashok.raj@intel.com> Cc: Andi Kleen <andi.kleen@intel.com> Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com> Cc: Stephane Eranian <eranian@google.com> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Link: https://lkml.kernel.org/r/20190623132434.447880978@linutronix.de
| * | | | | | | | | | | | x86/hpet: Remove pointless x86-64 specific #includeThomas Gleixner2019-06-281-4/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Nothing requires asm/pgtable.h here anymore. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> Cc: Ashok Raj <ashok.raj@intel.com> Cc: Andi Kleen <andi.kleen@intel.com> Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com> Cc: Stephane Eranian <eranian@google.com> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Link: https://lkml.kernel.org/r/20190623132434.339011567@linutronix.de
| * | | | | | | | | | | | x86/hpet: Restructure init codeThomas Gleixner2019-06-281-38/+43
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As a preparatory change for further consolidation, restructure the HPET init code so it becomes more readable. Fix up misleading and stale comments and rename variables so they actually make sense. No intended functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> Cc: Ashok Raj <ashok.raj@intel.com> Cc: Andi Kleen <andi.kleen@intel.com> Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com> Cc: Stephane Eranian <eranian@google.com> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Link: https://lkml.kernel.org/r/20190623132434.247842972@linutronix.de
| * | | | | | | | | | | | x86/hpet: Replace printk(KERN...) with pr_...()Thomas Gleixner2019-06-281-26/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | And sanitize the format strings while at it. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> Cc: Ashok Raj <ashok.raj@intel.com> Cc: Andi Kleen <andi.kleen@intel.com> Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com> Cc: Stephane Eranian <eranian@google.com> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Link: https://lkml.kernel.org/r/20190623132434.140411339@linutronix.de
| * | | | | | | | | | | | x86/hpet: Simplify CPU online codeThomas Gleixner2019-06-281-29/+2
| |/ / / / / / / / / / / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The indirection via work scheduled on the upcoming CPU was necessary with the old hotplug code because the online callback was invoked on the control CPU not on the upcoming CPU. The rework of the CPU hotplug core guarantees that the online callbacks are invoked on the upcoming CPU. Remove the now pointless work redirection. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> Cc: Ashok Raj <ashok.raj@intel.com> Cc: Andi Kleen <andi.kleen@intel.com> Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com> Cc: Stephane Eranian <eranian@google.com> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Link: https://lkml.kernel.org/r/20190623132434.047254075@linutronix.de
* | | | | | | | | | | | Merge branch 'x86-cpu-for-linus' of ↵Linus Torvalds2019-07-0812-44/+477
|\ \ \ \ \ \ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 CPU feature updates from Thomas Gleixner: "Updates for x86 CPU features: - Support for UMWAIT/UMONITOR, which allows to use MWAIT and MONITOR instructions in user space to save power e.g. in HPC workloads which spin wait on synchronization points. The maximum time a MWAIT can halt in userspace is controlled by the kernel and can be adjusted by the sysadmin. - Speed up the MTRR handling code on CPUs which support cache self-snooping correctly. On those CPUs the wbinvd() invocations can be omitted which speeds up the MTRR setup by a factor of 50. - Support for the new x86 vendor Zhaoxin who develops processors based on the VIA Centaur technology. - Prevent 'cat /proc/cpuinfo' from affecting isolated NOHZ_FULL CPUs by sending IPIs to retrieve the CPU frequency and use the cached values instead. - The addition and late revert of the FSGSBASE support. The revert was required as it turned out that the code still has hard to diagnose issues. Yet another engineering trainwreck... - Small fixes, cleanups, improvements and the usual new Intel CPU family/model addons" * 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (41 commits) x86/fsgsbase: Revert FSGSBASE support selftests/x86/fsgsbase: Fix some test case bugs x86/entry/64: Fix and clean up paranoid_exit x86/entry/64: Don't compile ignore_sysret if 32-bit emulation is enabled selftests/x86: Test SYSCALL and SYSENTER manually with TF set x86/mtrr: Skip cache flushes on CPUs with cache self-snooping x86/cpu/intel: Clear cache self-snoop capability in CPUs with known errata Documentation/ABI: Document umwait control sysfs interfaces x86/umwait: Add sysfs interface to control umwait maximum time x86/umwait: Add sysfs interface to control umwait C0.2 state x86/umwait: Initialize umwait control values x86/cpufeatures: Enumerate user wait instructions x86/cpu: Disable frequency requests via aperfmperf IPI for nohz_full CPUs x86/acpi/cstate: Add Zhaoxin processors support for cache flush policy in C3 ACPI, x86: Add Zhaoxin processors support for NONSTOP TSC x86/cpu: Create Zhaoxin processors architecture support file x86/cpu: Split Tremont based Atoms from the rest Documentation/x86/64: Add documentation for GS/FS addressing mode x86/elf: Enumerate kernel FSGSBASE capability in AT_HWCAP2 x86/cpu: Enable FSGSBASE on 64bit by default and add a chicken bit ...
| * | | | | | | | | | | | x86/fsgsbase: Revert FSGSBASE supportThomas Gleixner2019-07-032-129/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The FSGSBASE series turned out to have serious bugs and there is still an open issue which is not fully understood yet. The confidence in those changes has become close to zero especially as the test cases which have been shipped with that series were obviously never run before sending the final series out to LKML. ./fsgsbase_64 >/dev/null Segmentation fault As the merge window is close, the only sane decision is to revert FSGSBASE support. The revert is necessary as this branch has been merged into perf/core already and rebasing all of that a few days before the merge window is not the most brilliant idea. I could definitely slap myself for not noticing the test case fail when merging that series, but TBH my expectations weren't that low back then. Won't happen again. Revert the following commits: 539bca535dec ("x86/entry/64: Fix and clean up paranoid_exit") 2c7b5ac5d5a9 ("Documentation/x86/64: Add documentation for GS/FS addressing mode") f987c955c745 ("x86/elf: Enumerate kernel FSGSBASE capability in AT_HWCAP2") 2032f1f96ee0 ("x86/cpu: Enable FSGSBASE on 64bit by default and add a chicken bit") 5bf0cab60ee2 ("x86/entry/64: Document GSBASE handling in the paranoid path") 708078f65721 ("x86/entry/64: Handle FSGSBASE enabled paranoid entry/exit") 79e1932fa3ce ("x86/entry/64: Introduce the FIND_PERCPU_BASE macro") 1d07316b1363 ("x86/entry/64: Switch CR3 before SWAPGS in paranoid entry") f60a83df4593 ("x86/process/64: Use FSGSBASE instructions on thread copy and ptrace") 1ab5f3f7fe3d ("x86/process/64: Use FSBSBASE in switch_to() if available") a86b4625138d ("x86/fsgsbase/64: Enable FSGSBASE instructions in helper functions") 8b71340d702e ("x86/fsgsbase/64: Add intrinsics for FSGSBASE instructions") b64ed19b93c3 ("x86/cpu: Add 'unsafe_fsgsbase' to enable CR4.FSGSBASE") Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Ingo Molnar <mingo@kernel.org> Cc: Chang S. Bae <chang.seok.bae@intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Andi Kleen <ak@linux.intel.com> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: H. Peter Anvin <hpa@zytor.com>
| * | | | | | | | | | | | x86/mtrr: Skip cache flushes on CPUs with cache self-snoopingRicardo Neri2019-06-281-2/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Programming MTRR registers in multi-processor systems is a rather lengthy process. Furthermore, all processors must program these registers in lock step and with interrupts disabled; the process also involves flushing caches and TLBs twice. As a result, the process may take a considerable amount of time. On some platforms, this can lead to a large skew of the refined-jiffies clock source. Early when booting, if no other clock is available (e.g., booting with hpet=disabled), the refined-jiffies clock source is used to monitor the TSC clock source. If the skew of refined-jiffies is too large, Linux wrongly assumes that the TSC is unstable: clocksource: timekeeping watchdog on CPU1: Marking clocksource 'tsc-early' as unstable because the skew is too large: clocksource: 'refined-jiffies' wd_now: fffedc10 wd_last: fffedb90 mask: ffffffff clocksource: 'tsc-early' cs_now: 5eccfddebc cs_last: 5e7e3303d4 mask: ffffffffffffffff tsc: Marking TSC unstable due to clocksource watchdog As per measurements, around 98% of the time needed by the procedure to program MTRRs in multi-processor systems is spent flushing caches with wbinvd(). As per the Section 11.11.8 of the Intel 64 and IA 32 Architectures Software Developer's Manual, it is not necessary to flush caches if the CPU supports cache self-snooping. Thus, skipping the cache flushes can reduce by several tens of milliseconds the time needed to complete the programming of the MTRR registers: Platform Before After 104-core (208 Threads) Skylake 1437ms 28ms 2-core ( 4 Threads) Haswell 114ms 2ms Reported-by: Mohammad Etemadi <mohammad.etemadi@intel.com> Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Borislav Petkov <bp@suse.de> Cc: Alan Cox <alan.cox@intel.com> Cc: Tony Luck <tony.luck@intel.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Andi Kleen <andi.kleen@intel.com> Cc: Hans de Goede <hdegoede@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jordan Borgner <mail@jordan-borgner.de> Cc: "Ravi V. Shankar" <ravi.v.shankar@intel.com> Cc: Ricardo Neri <ricardo.neri@intel.com> Cc: Andy Shevchenko <andriy.shevchenko@intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Peter Feiner <pfeiner@google.com> Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com> Link: https://lkml.kernel.org/r/1561689337-19390-3-git-send-email-ricardo.neri-calderon@linux.intel.com
| * | | | | | | | | | | | x86/cpu/intel: Clear cache self-snoop capability in CPUs with known errataRicardo Neri2019-06-281-0/+27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Processors which have self-snooping capability can handle conflicting memory type across CPUs by snooping its own cache. However, there exists CPU models in which having conflicting memory types still leads to unpredictable behavior, machine check errors, or hangs. Clear this feature on affected CPUs to prevent its use. Suggested-by: Alan Cox <alan.cox@intel.com> Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Borislav Petkov <bp@suse.de> Cc: Tony Luck <tony.luck@intel.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Andi Kleen <andi.kleen@intel.com> Cc: Hans de Goede <hdegoede@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jordan Borgner <mail@jordan-borgner.de> Cc: "Ravi V. Shankar" <ravi.v.shankar@intel.com> Cc: Mohammad Etemadi <mohammad.etemadi@intel.com> Cc: Ricardo Neri <ricardo.neri@intel.com> Cc: Andy Shevchenko <andriy.shevchenko@intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Peter Feiner <pfeiner@google.com> Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com> Link: https://lkml.kernel.org/r/1561689337-19390-2-git-send-email-ricardo.neri-calderon@linux.intel.com
| * | | | | | | | | | | | x86/umwait: Add sysfs interface to control umwait maximum timeFenghua Yu2019-06-241-0/+36
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | IA32_UMWAIT_CONTROL[31:2] determines the maximum time in TSC-quanta that processor can stay in C0.1 or C0.2. A zero value means no maximum time. Each instruction sets its own deadline in the instruction's implicit input EDX:EAX value. The instruction wakes up if the time-stamp counter reaches or exceeds the specified deadline, or the umwait maximum time expires, or a store happens in the monitored address range in umwait. The administrator can write an unsigned 32-bit number to /sys/devices/system/cpu/umwait_control/max_time to change the default value. Note that a value of zero means there is no limit. The lower two bits of the value must be zero. [ tglx: Simplify the write function. Massage changelog ] Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ashok Raj <ashok.raj@intel.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Cc: "Borislav Petkov" <bp@alien8.de> Cc: "H Peter Anvin" <hpa@zytor.com> Cc: "Andy Lutomirski" <luto@kernel.org> Cc: "Peter Zijlstra" <peterz@infradead.org> Cc: "Ravi V Shankar" <ravi.v.shankar@intel.com> Link: https://lkml.kernel.org/r/1560994438-235698-5-git-send-email-fenghua.yu@intel.com
| * | | | | | | | | | | | x86/umwait: Add sysfs interface to control umwait C0.2 stateFenghua Yu2019-06-241-8/+110
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | C0.2 state in umwait and tpause instructions can be enabled or disabled on a processor through IA32_UMWAIT_CONTROL MSR register. By default, C0.2 is enabled and the user wait instructions results in lower power consumption with slower wakeup time. But in real time systems which require faster wakeup time although power savings could be smaller, the administrator needs to disable C0.2 and all umwait invocations from user applications use C0.1. Create a sysfs interface which allows the administrator to control C0.2 state during run time. Andy Lutomirski suggested to turn off local irqs before writing the MSR to ensure the cached control value is not changed by a concurrent sysfs write from a different CPU via IPI. [ tglx: Simplified the update logic in the write function and got rid of all the convoluted type casts. Added a shared update function and made the namespace consistent. Moved the sysfs create invocation. Massaged changelog ] Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ashok Raj <ashok.raj@intel.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Cc: "Borislav Petkov" <bp@alien8.de> Cc: "H Peter Anvin" <hpa@zytor.com> Cc: "Andy Lutomirski" <luto@kernel.org> Cc: "Peter Zijlstra" <peterz@infradead.org> Cc: "Ravi V Shankar" <ravi.v.shankar@intel.com> Link: https://lkml.kernel.org/r/1560994438-235698-4-git-send-email-fenghua.yu@intel.com
| * | | | | | | | | | | | x86/umwait: Initialize umwait control valuesFenghua Yu2019-06-242-0/+63
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | umwait or tpause allows the processor to enter a light-weight power/performance optimized state (C0.1 state) or an improved power/performance optimized state (C0.2 state) for a period specified by the instruction or until the system time limit or until a store to the monitored address range in umwait. IA32_UMWAIT_CONTROL MSR register allows the OS to enable/disable C0.2 on the processor and to set the maximum time the processor can reside in C0.1 or C0.2. By default C0.2 is enabled so the user wait instructions can enter the C0.2 state to save more power with slower wakeup time. Andy Lutomirski proposed to set the maximum umwait time to 100000 cycles by default. A quote from Andy: "What I want to avoid is the case where it works dramatically differently on NO_HZ_FULL systems as compared to everything else. Also, UMWAIT may behave a bit differently if the max timeout is hit, and I'd like that path to get exercised widely by making it happen even on default configs." A sysfs interface to adjust the time and the C0.2 enablement is provided in a follow up change. [ tglx: Renamed MSR_IA32_UMWAIT_CONTROL_MAX_TIME to MSR_IA32_UMWAIT_CONTROL_TIME_MASK because the constant is used as mask throughout the code. Massaged comments and changelog ] Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ashok Raj <ashok.raj@intel.com> Reviewed-by: Andy Lutomirski <luto@kernel.org> Cc: "Borislav Petkov" <bp@alien8.de> Cc: "H Peter Anvin" <hpa@zytor.com> Cc: "Peter Zijlstra" <peterz@infradead.org> Cc: "Tony Luck" <tony.luck@intel.com> Cc: "Ravi V Shankar" <ravi.v.shankar@intel.com> Link: https://lkml.kernel.org/r/1560994438-235698-3-git-send-email-fenghua.yu@intel.com
| * | | | | | | | | | | | x86/cpu: Disable frequency requests via aperfmperf IPI for nohz_full CPUsKonstantin Khlebnikov2019-06-221-1/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since commit 7d5905dc14a8 ("x86 / CPU: Always show current CPU frequency in /proc/cpuinfo") open and read of /proc/cpuinfo sends IPI to all CPUs. Many applications read /proc/cpuinfo at the start for trivial reasons like counting cores or detecting cpu features. While sensitive workloads like DPDK network polling don't like any interrupts. Integrates this feature with cpu isolation and do not send IPIs to CPUs without housekeeping flag HK_FLAG_MISC (set by nohz_full). Code that requests cpu frequency like show_cpuinfo() falls back to the last frequency set by the cpufreq driver if this method returns 0. Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Len Brown <len.brown@intel.com> Cc: Frederic Weisbecker <frederic@kernel.org> Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Link: https://lkml.kernel.org/r/155790354043.1104.15333317408370209.stgit@buzz
| * | | | | | | | | | | | x86/acpi/cstate: Add Zhaoxin processors support for cache flush policy in C3Tony W Wang-oc2019-06-221-0/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Same as Intel, Zhaoxin MP CPUs support C3 share cache and on all recent Zhaoxin platforms ARB_DISABLE is a nop. So set related flags correctly in the same way as Intel does. Signed-off-by: Tony W Wang-oc <TonyWWang-oc@zhaoxin.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: "hpa@zytor.com" <hpa@zytor.com> Cc: "gregkh@linuxfoundation.org" <gregkh@linuxfoundation.org> Cc: "rjw@rjwysocki.net" <rjw@rjwysocki.net> Cc: "lenb@kernel.org" <lenb@kernel.org> Cc: David Wang <DavidWang@zhaoxin.com> Cc: "Cooper Yan(BJ-RD)" <CooperYan@zhaoxin.com> Cc: "Qiyuan Wang(BJ-RD)" <QiyuanWang@zhaoxin.com> Cc: "Herry Yang(BJ-RD)" <HerryYang@zhaoxin.com> Link: https://lkml.kernel.org/r/a370503660994669991a7f7cda7c5e98@zhaoxin.com
| * | | | | | | | | | | | x86/cpu: Create Zhaoxin processors architecture support fileTony W Wang-oc2019-06-222-0/+168
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add x86 architecture support for new Zhaoxin processors. Carve out initialization code needed by Zhaoxin processors into a separate compilation unit. To identify Zhaoxin CPU, add a new vendor type X86_VENDOR_ZHAOXIN for system recognition. Signed-off-by: Tony W Wang-oc <TonyWWang-oc@zhaoxin.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: "hpa@zytor.com" <hpa@zytor.com> Cc: "gregkh@linuxfoundation.org" <gregkh@linuxfoundation.org> Cc: "rjw@rjwysocki.net" <rjw@rjwysocki.net> Cc: "lenb@kernel.org" <lenb@kernel.org> Cc: David Wang <DavidWang@zhaoxin.com> Cc: "Cooper Yan(BJ-RD)" <CooperYan@zhaoxin.com> Cc: "Qiyuan Wang(BJ-RD)" <QiyuanWang@zhaoxin.com> Cc: "Herry Yang(BJ-RD)" <HerryYang@zhaoxin.com> Link: https://lkml.kernel.org/r/01042674b2f741b2aed1f797359bdffb@zhaoxin.com
| * | | | | | | | | | | | x86/elf: Enumerate kernel FSGSBASE capability in AT_HWCAP2Andi Kleen2019-06-221-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The kernel needs to explicitly enable FSGSBASE. So, the application needs to know if it can safely use these instructions. Just looking at the CPUID bit is not enough because it may be running in a kernel that does not enable the instructions. One way for the application would be to just try and catch the SIGILL. But that is difficult to do in libraries which may not want to overwrite the signal handlers of the main application. Enumerate the enabled FSGSBASE capability in bit 1 of AT_HWCAP2 in the ELF aux vector. AT_HWCAP2 is already used by PPC for similar purposes. The application can access it open coded or by using the getauxval() function in newer versions of glibc. [ tglx: Massaged changelog ] Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Link: https://lkml.kernel.org/r/1557309753-24073-18-git-send-email-chang.seok.bae@intel.com
| * | | | | | | | | | | | x86/cpu: Enable FSGSBASE on 64bit by default and add a chicken bitAndy Lutomirski2019-06-221-18/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now that FSGSBASE is fully supported, remove unsafe_fsgsbase, enable FSGSBASE by default, and add nofsgsbase to disable it. Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Andi Kleen <ak@linux.intel.com> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Link: https://lkml.kernel.org/r/1557309753-24073-17-git-send-email-chang.seok.bae@intel.com
| * | | | | | | | | | | | x86/process/64: Use FSGSBASE instructions on thread copy and ptraceChang S. Bae2019-06-221-6/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When FSGSBASE is enabled, copying threads and reading fsbase and gsbase using ptrace must read the actual values. When copying a thread, use save_fsgs() and copy the saved values. For ptrace, the bases must be read from memory regardless of the selector if FSGSBASE is enabled. [ tglx: Invoke __rdgsbase_inactive() with interrupts disabled ] [ luto: Massage changelog ] Suggested-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: "H . Peter Anvin" <hpa@zytor.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Link: https://lkml.kernel.org/r/1557309753-24073-9-git-send-email-chang.seok.bae@intel.com
| * | | | | | | | | | | | x86/process/64: Use FSBSBASE in switch_to() if availableAndy Lutomirski2019-06-221-6/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With the new FSGSBASE instructions, FS and GSABSE can be efficiently read and writen in __switch_to(). Use that capability to preserve the full state. This will enable user code to do whatever it wants with the new instructions without any kernel-induced gotchas. (There can still be architectural gotchas: movl %gs,%eax; movl %eax,%gs may change GSBASE if WRGSBASE was used, but users are expected to read the CPU manual before doing things like that.) This is a considerable speedup. It seems to save about 100 cycles per context switch compared to the baseline 4.6-rc1 behavior on a Skylake laptop. [ chang: 5~10% performance improvements were seen with a context switch benchmark that ran threads with different FS/GSBASE values (to the baseline 4.16). Minor edit on the changelog. ] [ tglx: Masaage changelog ] Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Andi Kleen <ak@linux.intel.com> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Link: https://lkml.kernel.org/r/1557309753-24073-8-git-send-email-chang.seok.bae@intel.com
| * | | | | | | | | | | | x86/fsgsbase/64: Enable FSGSBASE instructions in helper functionsChang S. Bae2019-06-221-0/+66
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add cpu feature conditional FSGSBASE access to the relevant helper functions. That allows to accelerate certain FS/GS base operations in subsequent changes. Note, that while possible, the user space entry/exit GSBASE operations are not going to use the new FSGSBASE instructions. The reason is that it would require additional storage for the user space value which adds more complexity to the low level code and experiments have shown marginal benefit. This may be revisited later but for now the SWAPGS based handling in the entry code is preserved except for the paranoid entry/exit code. To preserve the SWAPGS entry mechanism introduce __[rd|wr]gsbase_inactive() helpers. Note, for Xen PV, paravirt hooks can be added later as they might allow a very efficient but different implementation. [ tglx: Massaged changelog ] Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Andi Kleen <ak@linux.intel.com> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Cc: Andrew Cooper <andrew.cooper3@citrix.com> Cc: H. Peter Anvin <hpa@zytor.com> Link: https://lkml.kernel.org/r/1557309753-24073-7-git-send-email-chang.seok.bae@intel.com
| * | | | | | | | | | | | x86/cpu: Add 'unsafe_fsgsbase' to enable CR4.FSGSBASEAndy Lutomirski2019-06-221-0/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is temporary. It will allow the next few patches to be tested incrementally. Setting unsafe_fsgsbase is a root hole. Don't do it. Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Andi Kleen <ak@linux.intel.com> Reviewed-by: Andy Lutomirski <luto@kernel.org> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: H. Peter Anvin <hpa@zytor.com> Link: https://lkml.kernel.org/r/1557309753-24073-4-git-send-email-chang.seok.bae@intel.com
| * | | | | | | | | | | | x86/ptrace: Prevent ptrace from clearing the FS/GS selectorChang S. Bae2019-06-221-12/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When a ptracer writes a ptracee's FS/GSBASE with a different value, the selector is also cleared. This behavior is not correct as the selector should be preserved. Update only the base value and leave the selector intact. To simplify the code further remove the conditional checking for the same value as this code is not performance critical. The only recognizable downside of this change is when the selector is already nonzero on write. The base will be reloaded according to the selector. But the case is highly unexpected in real usages. [ tglx: Massage changelog ] Suggested-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: "H . Peter Anvin" <hpa@zytor.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Link: https://lkml.kernel.org/r/9040CFCD-74BD-4C17-9A01-B9B713CF6B10@intel.com
| * | | | | | | | | | | | x86/cpufeatures: Enumerate the new AVX512 BFLOAT16 instructionsFenghua Yu2019-06-202-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | AVX512 BFLOAT16 instructions support 16-bit BFLOAT16 floating-point format (BF16) for deep learning optimization. BF16 is a short version of 32-bit single-precision floating-point format (FP32) and has several advantages over 16-bit half-precision floating-point format (FP16). BF16 keeps FP32 accumulation after multiplication without loss of precision, offers more than enough range for deep learning training tasks, and doesn't need to handle hardware exception. AVX512 BFLOAT16 instructions are enumerated in CPUID.7.1:EAX[bit 5] AVX512_BF16. CPUID.7.1:EAX contains only feature bits. Reuse the currently empty word 12 as a pure features word to hold the feature bits including AVX512_BF16. Detailed information of the CPUID bit and AVX512 BFLOAT16 instructions can be found in the latest Intel Architecture Instruction Set Extensions and Future Features Programming Reference. [ bp: Check CPUID(7) subleaf validity before accessing subleaf 1. ] Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: "Chang S. Bae" <chang.seok.bae@intel.com> Cc: Frederic Weisbecker <frederic@kernel.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jann Horn <jannh@google.com> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nadav Amit <namit@vmware.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Pavel Tatashin <pasha.tatashin@oracle.com> Cc: Peter Feiner <pfeiner@google.com> Cc: Radim Krcmar <rkrcmar@redhat.com> Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com> Cc: "Ravi V Shankar" <ravi.v.shankar@intel.com> Cc: Robert Hoo <robert.hu@linux.intel.com> Cc: "Sean J Christopherson" <sean.j.christopherson@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Thomas Lendacky <Thomas.Lendacky@amd.com> Cc: x86 <x86@kernel.org> Link: https://lkml.kernel.org/r/1560794416-217638-3-git-send-email-fenghua.yu@intel.com
| * | | | | | | | | | | | x86/cpufeatures: Combine word 11 and 12 into a new scattered features wordFenghua Yu2019-06-203-23/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It's a waste for the four X86_FEATURE_CQM_* feature bits to occupy two whole feature bits words. To better utilize feature words, re-define word 11 to host scattered features and move the four X86_FEATURE_CQM_* features into Linux defined word 11. More scattered features can be added in word 11 in the future. Rename leaf 11 in cpuid_leafs to CPUID_LNX_4 to reflect it's a Linux-defined leaf. Rename leaf 12 as CPUID_DUMMY which will be replaced by a meaningful name in the next patch when CPUID.7.1:EAX occupies world 12. Maximum number of RMID and cache occupancy scale are retrieved from CPUID.0xf.1 after scattered CQM features are enumerated. Carve out the code into a separate function. KVM doesn't support resctrl now. So it's safe to move the X86_FEATURE_CQM_* features to scattered features word 11 for KVM. Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Aaron Lewis <aaronlewis@google.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Babu Moger <babu.moger@amd.com> Cc: "Chang S. Bae" <chang.seok.bae@intel.com> Cc: "Sean J Christopherson" <sean.j.christopherson@intel.com> Cc: Frederic Weisbecker <frederic@kernel.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jann Horn <jannh@google.com> Cc: Juergen Gross <jgross@suse.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: kvm ML <kvm@vger.kernel.org> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Nadav Amit <namit@vmware.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Pavel Tatashin <pasha.tatashin@oracle.com> Cc: Peter Feiner <pfeiner@google.com> Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com> Cc: Ravi V Shankar <ravi.v.shankar@intel.com> Cc: Sherry Hurwitz <sherry.hurwitz@amd.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Thomas Lendacky <Thomas.Lendacky@amd.com> Cc: x86 <x86@kernel.org> Link: https://lkml.kernel.org/r/1560794416-217638-2-git-send-email-fenghua.yu@intel.com
| * | | | | | | | | | | | x86/cpufeatures: Carve out CQM features retrievalBorislav Petkov2019-06-201-27/+33
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ... into a separate function for better readability. Split out from a patch from Fenghua Yu <fenghua.yu@intel.com> to keep the mechanical, sole code movement separate for easy review. No functional changes. Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: x86@kernel.org
| * | | | | | | | | | | | x86/cacheinfo: Fix a -Wtype-limits warningQian Cai2019-06-191-2/+1
| | |_|_|_|/ / / / / / / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | cpuinfo_x86.x86_model is an unsigned type, so comparing against zero will generate a compilation warning: arch/x86/kernel/cpu/cacheinfo.c: In function 'cacheinfo_amd_init_llc_id': arch/x86/kernel/cpu/cacheinfo.c:662:19: warning: comparison is always true \ due to limited range of data type [-Wtype-limits] Remove the unnecessary lower bound check. [ bp: Massage. ] Fixes: 68091ee7ac3c ("x86/CPU/AMD: Calculate last level cache ID from number of sharing threads") Signed-off-by: Qian Cai <cai@lca.pw> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Sean Christopherson <sean.j.christopherson@intel.com> Cc: "Gustavo A. R. Silva" <gustavo@embeddedor.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Pu Wen <puwen@hygon.cn> Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: x86-ml <x86@kernel.org> Link: https://lkml.kernel.org/r/1560954773-11967-1-git-send-email-cai@lca.pw
* | | | | | | | | | | | Merge branch 'x86-fpu-for-linus' of ↵Linus Torvalds2019-07-084-58/+29
|\ \ \ \ \ \ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 FPU updates from Thomas Gleixner: "A small set of updates for the FPU code: - Make the no387/nofxsr command line options useful by restricting them to 32bit and actually clearing all dependencies to prevent random crashes and malfunction. - Simplify and cleanup the kernel_fpu_*() helpers" * 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/fpu: Inline fpu__xstate_clear_all_cpu_caps() x86/fpu: Make 'no387' and 'nofxsr' command line options useful x86/fpu: Remove the fpu__save() export x86/fpu: Simplify kernel_fpu_begin() x86/fpu: Simplify kernel_fpu_end()
| * | | | | | | | | | | | x86/fpu: Inline fpu__xstate_clear_all_cpu_caps()Sebastian Andrzej Siewior2019-07-072-11/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | All fpu__xstate_clear_all_cpu_caps() does is to invoke one simple function since commit 73e3a7d2a7c3b ("x86/fpu: Remove the explicit clearing of XSAVE dependent features") so invoke that function directly and remove the wrapper. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190704060743.rvew4yrjd6n33uzx@linutronix.de
| * | | | | | | | | | | | x86/fpu: Make 'no387' and 'nofxsr' command line options usefulSebastian Andrzej Siewior2019-07-072-10/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The command line option `no387' is designed to disable the FPU entirely. This only 'works' with CONFIG_MATH_EMULATION enabled. But on 64bit this cannot work because user space expects SSE to work which required basic FPU support. MATH_EMULATION does not help because SSE is not emulated. The command line option `nofxsr' should also be limited to 32bit because FXSR is part of the required flags on 64bit so turning it off is not possible. Clearing X86_FEATURE_FPU without emulation enabled will not work anyway and hang in fpu__init_system_early_generic() before the console is enabled. Setting additioal dependencies, ensures that the CPU still boots on a modern CPU. Otherwise, dropping FPU will leave FXSR enabled causing the kernel to crash early in fpu__init_system_mxcsr(). With XSAVE support it will crash in fpu__init_cpu_xstate(). The problem is that xsetbv() with XMM set and SSE cleared is not allowed. That means XSAVE has to be disabled. The XSAVE support is disabled in fpu__init_system_xstate_size_legacy() but it is too late. It can be removed, it has been added in commit 1f999ab5a1360 ("x86, xsave: Disable xsave in i387 emulation mode") to use `no387' on a CPU with XSAVE support. All this happens before console output. After hat, the next possible crash is in RAID6 detect code because MMX remained enabled. With a 3DNOW enabled config it will explode in memcpy() for instance due to kernel_fpu_begin() but this is unconditionally enabled. This is enough to boot a Debian Wheezy on a 32bit qemu "host" CPU which supports everything up to XSAVES, AVX2 without 3DNOW. Later, Debian increased the minimum requirements to i686 which means it does not boot userland atleast due to CMOV. After masking the additional features it still keeps SSE4A and 3DNOW* enabled (if present on the host) but those are unused in the kernel. Restrict `no387' and `nofxsr' otions to 32bit only. Add dependencies for FPU, FXSR to additionaly mask CMOV, MMX, XSAVE if FXSR or FPU is cleared. Reported-by: Vegard Nossum <vegard.nossum@oracle.com> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190703083247.57kjrmlxkai3vpw3@linutronix.de
| * | | | | | | | | | | | x86/fpu: Remove the fpu__save() exportChristoph Hellwig2019-06-171-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This function is only use by the core FPU code. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Dave Hansen <dave.hansen@intel.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Nicolai Stange <nstange@suse.de> Cc: Rik van Riel <riel@surriel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: x86-ml <x86@kernel.org> Link: https://lkml.kernel.org/r/20190604071524.12835-4-hch@lst.de
| * | | | | | | | | | | | x86/fpu: Simplify kernel_fpu_begin()Christoph Hellwig2019-06-171-24/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Merge two helpers into the main function, remove a pointless local variable and flatten a conditional. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Dave Hansen <dave.hansen@intel.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Nicolai Stange <nstange@suse.de> Cc: Rik van Riel <riel@surriel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: x86-ml <x86@kernel.org> Link: https://lkml.kernel.org/r/20190604071524.12835-3-hch@lst.de
| * | | | | | | | | | | | x86/fpu: Simplify kernel_fpu_end()Christoph Hellwig2019-06-171-12/+3
| | |_|/ / / / / / / / / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Remove two little helpers and merge them into kernel_fpu_end() to streamline the function. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Dave Hansen <dave.hansen@intel.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Nicolai Stange <nstange@suse.de> Cc: Rik van Riel <riel@surriel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: x86-ml <x86@kernel.org> Link: https://lkml.kernel.org/r/20190604071524.12835-2-hch@lst.de
* | | | | | | | | | | | Merge branch 'x86-apic-for-linus' of ↵Linus Torvalds2019-07-0815-62/+193
|\ \ \ \ \ \ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x96 apic updates from Thomas Gleixner: "Updates for the x86 APIC interrupt handling and APIC timer: - Fix a long standing issue with spurious interrupts which was caused by the big vector management rework a few years ago. Robert Hodaszi provided finally enough debug data and an excellent initial failure analysis which allowed to understand the underlying issues. This contains a change to the core interrupt management code which is required to handle this correctly for the APIC/IO_APIC. The core changes are NOOPs for most architectures except ARM64. ARM64 is not impacted by the change as confirmed by Marc Zyngier. - Newer systems allow to disable the PIT clock for power saving causing panic in the timer interrupt delivery check of the IO/APIC when the HPET timer is not enabled either. While the clock could be turned on this would cause an endless whack a mole game to chase the proper register in each affected chipset. These systems provide the relevant frequencies for TSC, CPU and the local APIC timer via CPUID and/or MSRs, which allows to avoid the PIT/HPET based calibration. As the calibration code is the only usage of the legacy timers on modern systems and is skipped anyway when the frequencies are known already, there is no point in setting up the PIT and actually checking for the interrupt delivery via IO/APIC. To achieve this on a wide variety of platforms, the CPUID/MSR based frequency readout has been made more robust, which also allowed to remove quite some workarounds which turned out to be not longer required. Thanks to Daniel Drake for analysis, patches and verification" * 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/irq: Seperate unused system vectors from spurious entry again x86/irq: Handle spurious interrupt after shutdown gracefully x86/ioapic: Implement irq_get_irqchip_state() callback genirq: Add optional hardware synchronization for shutdown genirq: Fix misleading synchronize_irq() documentation genirq: Delay deactivation in free_irq() x86/timer: Skip PIT initialization on modern chipsets x86/apic: Use non-atomic operations when possible x86/apic: Make apic_bsp_setup() static x86/tsc: Set LAPIC timer period to crystal clock frequency x86/apic: Rename 'lapic_timer_frequency' to 'lapic_timer_period' x86/tsc: Use CPUID.0x16 to calculate missing crystal frequency
| * | | | | | | | | | | | x86/irq: Seperate unused system vectors from spurious entry againThomas Gleixner2019-07-032-12/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Quite some time ago the interrupt entry stubs for unused vectors in the system vector range got removed and directly mapped to the spurious interrupt vector entry point. Sounds reasonable, but it's subtly broken. The spurious interrupt vector entry point pushes vector number 0xFF on the stack which makes the whole logic in __smp_spurious_interrupt() pointless. As a consequence any spurious interrupt which comes from a vector != 0xFF is treated as a real spurious interrupt (vector 0xFF) and not acknowledged. That subsequently stalls all interrupt vectors of equal and lower priority, which brings the system to a grinding halt. This can happen because even on 64-bit the system vector space is not guaranteed to be fully populated. A full compile time handling of the unused vectors is not possible because quite some of them are conditonally populated at runtime. Bring the entry stubs back, which wastes 160 bytes if all stubs are unused, but gains the proper handling back. There is no point to selectively spare some of the stubs which are known at compile time as the required code in the IDT management would be way larger and convoluted. Do not route the spurious entries through common_interrupt and do_IRQ() as the original code did. Route it to smp_spurious_interrupt() which evaluates the vector number and acts accordingly now that the real vector numbers are handed in. Fixup the pr_warn so the actual spurious vector (0xff) is clearly distiguished from the other vectors and also note for the vectored case whether it was pending in the ISR or not. "Spurious APIC interrupt (vector 0xFF) on CPU#0, should never happen." "Spurious interrupt vector 0xed on CPU#1. Acked." "Spurious interrupt vector 0xee on CPU#1. Not pending!." Fixes: 2414e021ac8d ("x86: Avoid building unused IRQ entry stubs") Reported-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Jan Beulich <jbeulich@suse.com> Link: https://lkml.kernel.org/r/20190628111440.550568228@linutronix.de
| * | | | | | | | | | | | x86/irq: Handle spurious interrupt after shutdown gracefullyThomas Gleixner2019-07-032-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since the rework of the vector management, warnings about spurious interrupts have been reported. Robert provided some more information and did an initial analysis. The following situation leads to these warnings: CPU 0 CPU 1 IO_APIC interrupt is raised sent to CPU1 Unable to handle immediately (interrupts off, deep idle delay) mask() ... free() shutdown() synchronize_irq() clear_vector() do_IRQ() -> vector is clear Before the rework the vector entries of legacy interrupts were statically assigned and occupied precious vector space while most of them were unused. Due to that the above situation was handled silently because the vector was handled and the core handler of the assigned interrupt descriptor noticed that it is shut down and returned. While this has been usually observed with legacy interrupts, this situation is not limited to them. Any other interrupt source, e.g. MSI, can cause the same issue. After adding proper synchronization for level triggered interrupts, this can only happen for edge triggered interrupts where the IO-APIC obviously cannot provide information about interrupts in flight. While the spurious warning is actually harmless in this case it worries users and driver developers. Handle it gracefully by marking the vector entry as VECTOR_SHUTDOWN instead of VECTOR_UNUSED when the vector is freed up. If that above late handling happens the spurious detector will not complain and switch the entry to VECTOR_UNUSED. Any subsequent spurious interrupt on that line will trigger the spurious warning as before. Fixes: 464d12309e1b ("x86/vector: Switch IOAPIC to global reservation mode") Reported-by: Robert Hodaszi <Robert.Hodaszi@digi.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>- Tested-by: Robert Hodaszi <Robert.Hodaszi@digi.com> Cc: Marc Zyngier <marc.zyngier@arm.com> Link: https://lkml.kernel.org/r/20190628111440.459647741@linutronix.de
| * | | | | | | | | | | | x86/ioapic: Implement irq_get_irqchip_state() callbackThomas Gleixner2019-07-031-0/+46
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When an interrupt is shut down in free_irq() there might be an inflight interrupt pending in the IO-APIC remote IRR which is not yet serviced. That means the interrupt has been sent to the target CPUs local APIC, but the target CPU is in a state which delays the servicing. So free_irq() would proceed to free resources and to clear the vector because synchronize_hardirq() does not see an interrupt handler in progress. That can trigger a spurious interrupt warning, which is harmless and just confuses users, but it also can leave the remote IRR in a stale state because once the handler is invoked the interrupt resources might be freed already and therefore acknowledgement is not possible anymore. Implement the irq_get_irqchip_state() callback for the IO-APIC irq chip. The callback is invoked from free_irq() via __synchronize_hardirq(). Check the remote IRR bit of the interrupt and return 'in flight' if it is set and the interrupt is configured in level mode. For edge mode the remote IRR has no meaning. As this is only meaningful for level triggered interrupts this won't cure the potential spurious interrupt warning for edge triggered interrupts, but the edge trigger case does not result in stale hardware state. This has to be addressed at the vector/interrupt entry level seperately. Fixes: 464d12309e1b ("x86/vector: Switch IOAPIC to global reservation mode") Reported-by: Robert Hodaszi <Robert.Hodaszi@digi.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Marc Zyngier <marc.zyngier@arm.com> Link: https://lkml.kernel.org/r/20190628111440.370295517@linutronix.de
| * | | | | | | | | | | | x86/timer: Skip PIT initialization on modern chipsetsThomas Gleixner2019-06-294-3/+60
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Recent Intel chipsets including Skylake and ApolloLake have a special ITSSPRC register which allows the 8254 PIT to be gated. When gated, the 8254 registers can still be programmed as normal, but there are no IRQ0 timer interrupts. Some products such as the Connex L1430 and exone go Rugged E11 use this register to ship with the PIT gated by default. This causes Linux to fail to boot: Kernel panic - not syncing: IO-APIC + timer doesn't work! Boot with apic=debug and send a report. The panic happens before the framebuffer is initialized, so to the user, it appears as an early boot hang on a black screen. Affected products typically have a BIOS option that can be used to enable the 8254 and make Linux work (Chipset -> South Cluster Configuration -> Miscellaneous Configuration -> 8254 Clock Gating), however it would be best to make Linux support the no-8254 case. Modern sytems allow to discover the TSC and local APIC timer frequencies, so the calibration against the PIT is not required. These systems have always running timers and the local APIC timer works also in deep power states. So the setup of the PIT including the IO-APIC timer interrupt delivery checks are a pointless exercise. Skip the PIT setup and the IO-APIC timer interrupt checks on these systems, which avoids the panic caused by non ticking PITs and also speeds up the boot process. Thanks to Daniel for providing the changelog, initial analysis of the problem and testing against a variety of machines. Reported-by: Daniel Drake <drake@endlessm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Daniel Drake <drake@endlessm.com> Cc: bp@alien8.de Cc: hpa@zytor.com Cc: linux@endlessm.com Cc: rafael.j.wysocki@intel.com Cc: hdegoede@redhat.com Link: https://lkml.kernel.org/r/20190628072307.24678-1-drake@endlessm.com
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