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| * | | | | x86/intel_rdt: Make useful functions available internallyReinette Chatre2018-06-233-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In support of the work done to enable resource groups to have different modes some static functions need to be available for sharing amongst all RDT components. Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: fenghua.yu@intel.com Cc: tony.luck@intel.com Cc: vikas.shivappa@linux.intel.com Cc: gavin.hindman@intel.com Cc: jithu.joseph@intel.com Cc: dave.hansen@intel.com Cc: hpa@zytor.com Link: https://lkml.kernel.org/r/2af8fd6e937ae4fbdaa52dee1123823cb4993176.1529706536.git.reinette.chatre@intel.com
| * | | | | x86/intel_rdt: Introduce test to determine if closid is in useReinette Chatre2018-06-231-0/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | During CAT feature discovery the capacity bitmasks (CBMs) associated with all the classes of service are initialized to all ones, even if the class of service is not in use. Introduce a test that can be used to determine if a class of service is in use. This test enables code interested in parsing the CBMs to know if its values are meaningful or can be ignored. Temporarily mark the function as unused to silence compile warnings until it is used. Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: fenghua.yu@intel.com Cc: tony.luck@intel.com Cc: vikas.shivappa@linux.intel.com Cc: gavin.hindman@intel.com Cc: jithu.joseph@intel.com Cc: dave.hansen@intel.com Cc: hpa@zytor.com Link: https://lkml.kernel.org/r/798f8d89cd9b12df492d48c14bdc8ee3b39b1c6f.1529706536.git.reinette.chatre@intel.com
| * | | | | x86/intel_rdt: Introduce resource group's mode resctrl fileReinette Chatre2018-06-231-0/+83
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A new resctrl file "mode" associated with each resource group is introduced. This file will display the resource group's current mode and an administrator can also use it to modify the resource group's mode. Only shareable mode is currently supported. Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: fenghua.yu@intel.com Cc: tony.luck@intel.com Cc: vikas.shivappa@linux.intel.com Cc: gavin.hindman@intel.com Cc: jithu.joseph@intel.com Cc: dave.hansen@intel.com Cc: hpa@zytor.com Link: https://lkml.kernel.org/r/20ab78fda26a8c8d98e18ec555f6a1f728948972.1529706536.git.reinette.chatre@intel.com
| * | | | | x86/intel_rdt: Associate mode with each RDT resource groupReinette Chatre2018-06-232-0/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Each RDT resource group is associated with a mode that will reflect the level of sharing of its allocations. The default, shareable, will be associated with each resource group on creation since it is zero and resource groups are created with kzalloc. The managing of the mode of a resource group will follow. The default resource group always remain though so ensure that it is reset to the default mode when the resctrl filesystem is unmounted. Also introduce a utility that can be used to determine the mode of a resource group when it is searched for based on its class of service. Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: fenghua.yu@intel.com Cc: tony.luck@intel.com Cc: vikas.shivappa@linux.intel.com Cc: gavin.hindman@intel.com Cc: jithu.joseph@intel.com Cc: dave.hansen@intel.com Cc: hpa@zytor.com Link: https://lkml.kernel.org/r/797e4e1de4e4fcdf5b5e0039354d6a28079e2015.1529706536.git.reinette.chatre@intel.com
| * | | | | x86/intel_rdt: Introduce RDT resource group modeReinette Chatre2018-06-231-0/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | At this time there are no constraints on how bitmasks represented by schemata can be associated with closids represented by resource groups. A bitmask of one class of service can without any objections overlap with the bitmask of another class of service. The concept of "mode" is introduced in preparation for support of control over whether cache regions can be shared between classes of service. At this time the only mode reflects the current cache allocations where all can potentially be shared. Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: fenghua.yu@intel.com Cc: tony.luck@intel.com Cc: vikas.shivappa@linux.intel.com Cc: gavin.hindman@intel.com Cc: jithu.joseph@intel.com Cc: dave.hansen@intel.com Cc: hpa@zytor.com Link: https://lkml.kernel.org/r/87e88275597fbfa03ea9d41c1186bf012c831c01.1529706536.git.reinette.chatre@intel.com
| * | | | | x86/intel_rdt: Provide pseudo-locking hooks within rdt_mountReinette Chatre2018-06-232-1/+18
| | |_|/ / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Stephen Rothwell reported that the Cache Pseudo-Locking enabling and the kernfs support for mounting with fs_context are conflicting. In preparation for a conflict-free merge between the two repos some no-op hooks are created within the RDT mount function being changed by the two features. The goal is for this commit to be placed on a minimal no-rebase branch to be consumed by both features. Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Suggested-by: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: fenghua.yu@intel.com Cc: tony.luck@intel.com Cc: vikas.shivappa@linux.intel.com Cc: gavin.hindman@intel.com Cc: jithu.joseph@intel.com Cc: dave.hansen@intel.com Cc: hpa@zytor.com Cc: David Howells <dhowells@redhat.com> Link: https://lkml.kernel.org/r/410697ead08978bd12111c0afc4ce9e7bd71a5fe.1529706536.git.reinette.chatre@intel.com
* | | | | Merge branch 'x86-cpu-for-linus' of ↵Linus Torvalds2018-08-131-1/+9
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cpu updates from Thomas Gleixner: "Two small updates for the CPU code: - Improve NUMA emulation - Add the EPT_AD CPU feature bit" * 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/cpufeatures: Add EPT_AD feature bit x86/numa_emulation: Introduce uniform split capability x86/numa_emulation: Fix emulated-to-physical node mapping
| * | | | | x86/cpufeatures: Add EPT_AD feature bitPeter Feiner2018-08-031-1/+9
| | |_|_|/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Some Intel processors have an EPT feature whereby the accessed & dirty bits in EPT entries can be updated by HW. MSR IA32_VMX_EPT_VPID_CAP exposes the presence of this capability. There is no point in trying to use that new feature bit in the VMX code as VMX needs to read the MSR anyway to access other bits, but having the feature bit for EPT_AD in place helps virtualization management as it exposes "ept_ad" in /proc/cpuinfo/$proc/flags if the feature is present. [ tglx: Amended changelog ] Signed-off-by: Peter Feiner <pfeiner@google.com> Signed-off-by: Peter Shier <pshier@google.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Jim Mattson <jmattson@google.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Borislav Petkov <bp@suse.de> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: David Woodhouse <dwmw@amazon.co.uk> Link: https://lkml.kernel.org/r/20180801180657.138051-1-pshier@google.com
* | | | | Merge branch 'ras-core-for-linus' of ↵Linus Torvalds2018-08-131-95/+107
|\ \ \ \ \ | |_|_|_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 RAS updates from Thomas Gleixner: "A small set of changes to the RAS core: - Rework of the MCE bank scanning code - Y2038 converion" * 'ras-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mce: Cleanup __mc_scan_banks() x86/mce: Carve out bank scanning code x86/mce: Remove !banks check x86/mce: Carve out the crashing_cpu check x86/mce: Always use 64-bit timestamps
| * | | | x86/mce: Cleanup __mc_scan_banks()Borislav Petkov2018-06-221-13/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Correct comments, improve readability, simplify. No functional changes. Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20180622095428.626-7-bp@alien8.de
| * | | | x86/mce: Carve out bank scanning codeBorislav Petkov2018-06-221-63/+71
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Carve out the scan loop into a separate function. No functional changes. Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20180622095428.626-6-bp@alien8.de
| * | | | x86/mce: Remove !banks checkBorislav Petkov2018-06-221-4/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If we don't have MCA banks, we won't see machine checks anyway. Drop the check. Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20180622095428.626-5-bp@alien8.de
| * | | | x86/mce: Carve out the crashing_cpu checkBorislav Petkov2018-06-221-27/+37
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Carve out the rendezvous handler timeout avoidance check into a separate function in order to simplify the #MC handler. No functional changes. Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20180622095428.626-4-bp@alien8.de
| * | | | x86/mce: Always use 64-bit timestampsArnd Bergmann2018-06-221-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The machine check timestamp uses get_seconds(), which returns an 'unsigned long' number that might overflow on 32-bit architectures (in the distant future) and is therefore deprecated. The normal replacement would be ktime_get_real_seconds(), but that needs to use a sequence lock that might cause a deadlock if the MCE happens at just the wrong moment. The __ktime_get_real_seconds() skips that lock and is safer here, but has a miniscule risk of returning the wrong time when we read it on a 32-bit architecture at the same time as updating the epoch, i.e. from before y2106 overflow time to after, or vice versa. This seems to be an acceptable risk in this particular case, and is the same thing we do in kdb. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: linux-edac <linux-edac@vger.kernel.org> Cc: y2038@lists.linaro.org Link: http://lkml.kernel.org/r/20180618100759.1921750-1-arnd@arndb.de
* | | | | x86/MCE: Remove min interval polling limitationDewet Thibaut2018-07-171-3/+0
| |_|_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit b3b7c4795c ("x86/MCE: Serialize sysfs changes") introduced a min interval limitation when setting the check interval for polled MCEs. However, the logic is that 0 disables polling for corrected MCEs, see Documentation/x86/x86_64/machinecheck. The limitation prevents disabling. Remove this limitation and allow the value 0 to disable polling again. Fixes: b3b7c4795c ("x86/MCE: Serialize sysfs changes") Signed-off-by: Dewet Thibaut <thibaut.dewet@nokia.com> Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com> [ Massage commit message. ] Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: linux-edac <linux-edac@vger.kernel.org> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20180716084927.24869-1-alexander.sverdlin@nokia.com
* | | | Merge branch 'x86-pti-for-linus' of ↵Linus Torvalds2018-07-082-4/+8
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86/pti updates from Thomas Gleixner: "Two small fixes correcting the handling of SSB mitigations on AMD processors" * 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/bugs: Fix the AMD SSBD usage of the SPEC_CTRL MSR x86/bugs: Update when to check for the LS_CFG SSBD mitigation
| * | | | x86/bugs: Fix the AMD SSBD usage of the SPEC_CTRL MSRTom Lendacky2018-07-031-3/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On AMD, the presence of the MSR_SPEC_CTRL feature does not imply that the SSBD mitigation support should use the SPEC_CTRL MSR. Other features could have caused the MSR_SPEC_CTRL feature to be set, while a different SSBD mitigation option is in place. Update the SSBD support to check for the actual SSBD features that will use the SPEC_CTRL MSR. Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Cc: Borislav Petkov <bpetkov@suse.de> Cc: David Woodhouse <dwmw@amazon.co.uk> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: 6ac2f49edb1e ("x86/bugs: Add AMD's SPEC_CTRL MSR usage") Link: http://lkml.kernel.org/r/20180702213602.29202.33151.stgit@tlendack-t1.amdoffice.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | x86/bugs: Update when to check for the LS_CFG SSBD mitigationTom Lendacky2018-07-031-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If either the X86_FEATURE_AMD_SSBD or X86_FEATURE_VIRT_SSBD features are present, then there is no need to perform the check for the LS_CFG SSBD mitigation support. Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Cc: Borislav Petkov <bpetkov@suse.de> Cc: David Woodhouse <dwmw@amazon.co.uk> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20180702213553.29202.21089.stgit@tlendack-t1.amdoffice.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | | | | x86/mtrr: Don't copy out-of-bounds data in mtrr_writeJann Horn2018-07-071-1/+2
| |_|/ / |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Don't access the provided buffer out of bounds - this can cause a kernel out-of-bounds read when invoked through sys_splice() or other things that use kernel_write()/__kernel_write(). Fixes: 7f8ec5a4f01a ("x86/mtrr: Convert to use strncpy_from_user() helper") Signed-off-by: Jann Horn <jannh@google.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180706215003.156702-1-jannh@google.com
* | | | Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds2018-06-243-2/+8
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Thomas Gleixner: "A set of fixes for x86: - Make Xen PV guest deal with speculative store bypass correctly - Address more fallout from the 5-Level pagetable handling. Undo an __initdata annotation to avoid section mismatch and malfunction when post init code would touch the freed variable. - Handle exception fixup in math_error() before calling notify_die(). The reverse call order incorrectly triggers notify_die() listeners for soemthing which is handled correctly at the site which issues the floating point instruction. - Fix an off by one in the LLC topology calculation on AMD - Handle non standard memory block sizes gracefully un UV platforms - Plug a memory leak in the microcode loader - Sanitize the purgatory build magic - Add the x86 specific device tree bindings directory to the x86 MAINTAINER file patterns" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mm: Fix 'no5lvl' handling Revert "x86/mm: Mark __pgtable_l5_enabled __initdata" x86/CPU/AMD: Fix LLC ID bit-shift calculation MAINTAINERS: Add file patterns for x86 device tree bindings x86/microcode/intel: Fix memleak in save_microcode_patch() x86/platform/UV: Add kernel parameter to set memory block size x86/platform/UV: Use new set memory block size function x86/platform/UV: Add adjustable set memory block size function x86/build: Remove unnecessary preparation for purgatory Revert "kexec/purgatory: Add clean-up for purgatory directory" x86/xen: Add call of speculative_store_bypass_ht_init() to PV paths x86: Call fixup_exception() before notify_die() in math_error()
| * | | | x86/mm: Fix 'no5lvl' handlingKirill A. Shutemov2018-06-231-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | early_identify_cpu() has to use early version of pgtable_l5_enabled() that doesn't rely on cpu_feature_enabled(). Defining USE_EARLY_PGTABLE_L5 before all includes does the trick. I lost the define in one of reworks of the original patch. Fixes: 372fddf70904 ("x86/mm: Introduce the 'no5lvl' kernel parameter") Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Link: https://lkml.kernel.org/r/20180622220841.54135-3-kirill.shutemov@linux.intel.com
| * | | | x86/CPU/AMD: Fix LLC ID bit-shift calculationSuravee Suthikulpanit2018-06-221-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The current logic incorrectly calculates the LLC ID from the APIC ID. Unless specified otherwise, the LLC ID should be calculated by removing the Core and Thread ID bits from the least significant end of the APIC ID. For more info, see "ApicId Enumeration Requirements" in any Fam17h PPR document. [ bp: Improve commit message. ] Fixes: 68091ee7ac3c ("Calculate last level cache ID from number of sharing threads") Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1528915390-30533-1-git-send-email-suravee.suthikulpanit@amd.com
| * | | | Merge branch 'linus' into x86/urgentThomas Gleixner2018-06-2220-125/+498
| |\ \ \ \ | | | |_|/ | | |/| | | | | | | Required to queue a dependent fix.
| * | | | x86/microcode/intel: Fix memleak in save_microcode_patch()Zhenzhong Duan2018-06-221-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Free useless ucode_patch entry when it's replaced. [ bp: Drop the memfree_patch() two-liner. ] Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Srinivas REDDY Eeda <srinivas.eeda@oracle.com> Link: http://lkml.kernel.org/r/888102f0-fd22-459d-b090-a1bd8a00cb2b@default
* | | | | Merge branch 'x86-pti-for-linus' of ↵Linus Torvalds2018-06-241-0/+4
|\ \ \ \ \ | | |_|/ / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 pti fixes from Thomas Gleixner: "Two small updates for the speculative distractions: - Make it more clear to the compiler that array_index_mask_nospec() is not subject for optimizations. It's not perfect, but ... - Don't report XEN PV guests as vulnerable because their mitigation state depends on the hypervisor. Report unknown and refer to the hypervisor requirement" * 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/spectre_v1: Disable compiler optimizations over array_index_mask_nospec() x86/pti: Don't report XenPV as vulnerable
| * | | | x86/pti: Don't report XenPV as vulnerableJiri Kosina2018-06-211-0/+4
| | |/ / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Xen PV domain kernel is not by design affected by meltdown as it's enforcing split CR3 itself. Let's not report such systems as "Vulnerable" in sysfs (we're also already forcing PTI to off in X86_HYPER_XEN_PV cases); the security of the system ultimately depends on presence of mitigation in the Hypervisor, which can't be easily detected from DomU; let's report that. Reported-and-tested-by: Mike Latimer <mlatimer@suse.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Juergen Gross <jgross@suse.com> Cc: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/nycvar.YFH.7.76.1806180959080.6203@cbobk.fhfr.pm [ Merge the user-visible string into a single line. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | | | Merge branch 'ras-urgent-for-linus' of ↵Linus Torvalds2018-06-242-16/+33
|\ \ \ \ | |/ / / |/| | / | | |/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull ras fixes from Thomas Gleixner: "A set of fixes for RAS/MCE: - Improve the error message when the kernel cannot recover from a MCE so the maximum amount of information gets provided. - Individually check MCE recovery features on SkyLake CPUs instead of assuming none when the CAPID0 register does not advertise the general ability for recovery. - Prevent MCE to output inconsistent messages which first show an error location and then claim that the source is unknown. - Prevent overwriting MCi_STATUS in the attempt to gather more information when a fatal MCE has alreay been detected. This leads to empty status values in the printout and failing to react promptly on the fatal event" * 'ras-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mce: Fix incorrect "Machine check from unknown source" message x86/mce: Do not overwrite MCi_STATUS in mce_no_way_out() x86/mce: Check for alternate indication of machine check recovery on Skylake x86/mce: Improve error message when kernel cannot recover
| * | x86/mce: Fix incorrect "Machine check from unknown source" messageTony Luck2018-06-221-8/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Some injection testing resulted in the following console log: mce: [Hardware Error]: CPU 22: Machine Check Exception: f Bank 1: bd80000000100134 mce: [Hardware Error]: RIP 10:<ffffffffc05292dd> {pmem_do_bvec+0x11d/0x330 [nd_pmem]} mce: [Hardware Error]: TSC c51a63035d52 ADDR 3234bc4000 MISC 88 mce: [Hardware Error]: PROCESSOR 0:50654 TIME 1526502199 SOCKET 0 APIC 38 microcode 2000043 mce: [Hardware Error]: Run the above through 'mcelog --ascii' Kernel panic - not syncing: Machine check from unknown source This confused everybody because the first line quite clearly shows that we found a logged error in "Bank 1", while the last line says "unknown source". The problem is that the Linux code doesn't do the right thing for a local machine check that results in a fatal error. It turns out that we know very early in the handler whether the machine check is fatal. The call to mce_no_way_out() has checked all the banks for the CPU that took the local machine check. If it says we must crash, we can do so right away with the right messages. We do scan all the banks again. This means that we might initially not see a problem, but during the second scan find something fatal. If this happens we print a slightly different message (so I can see if it actually every happens). [ bp: Remove unneeded severity assignment. ] Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Ashok Raj <ashok.raj@intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Qiuxu Zhuo <qiuxu.zhuo@intel.com> Cc: linux-edac <linux-edac@vger.kernel.org> Cc: stable@vger.kernel.org # 4.2 Link: http://lkml.kernel.org/r/52e049a497e86fd0b71c529651def8871c804df0.1527283897.git.tony.luck@intel.com
| * | x86/mce: Do not overwrite MCi_STATUS in mce_no_way_out()Borislav Petkov2018-06-221-8/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | mce_no_way_out() does a quick check during #MC to see whether some of the MCEs logged would require the kernel to panic immediately. And it passes a struct mce where MCi_STATUS gets written. However, after having saved a valid status value, the next iteration of the loop which goes over the MCA banks on the CPU, overwrites the valid status value because we're using struct mce as storage instead of a temporary variable. Which leads to MCE records with an empty status value: mce: [Hardware Error]: CPU 0: Machine Check Exception: 6 Bank 0: 0000000000000000 mce: [Hardware Error]: RIP 10:<ffffffffbd42fbd7> {trigger_mce+0x7/0x10} In order to prevent the loss of the status register value, return immediately when severity is a panic one so that we can panic immediately with the first fatal MCE logged. This is also the intention of this function and not to noodle over the banks while a fatal MCE is already logged. Tony: read the rest of the MCA bank to populate the struct mce fully. Suggested-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: <stable@vger.kernel.org> Link: https://lkml.kernel.org/r/20180622095428.626-8-bp@alien8.de
| * | x86/mce: Improve error message when kernel cannot recoverTony Luck2018-06-071-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since we added support to add recovery from some errors inside the kernel in: commit b2f9d678e28c ("x86/mce: Check for faults tagged in EXTABLE_CLASS_FAULT exception table entries") we have done a less than stellar job at reporting the cause of recoverable machine checks that occur in other parts of the kernel. The user just gets the unhelpful message: mce: [Hardware Error]: Machine check: Action required: unknown MCACOD doubly unhelpful when they check the manual for the reported IA32_MSR_STATUS.MCACOD and see that it is listed as one of the standard recoverable values. Add an extra rule to the MCE severity table to catch this case and report it as: mce: [Hardware Error]: Machine check: Data load in unrecoverable area of kernel Fixes: b2f9d678e28c ("x86/mce: Check for faults tagged in EXTABLE_CLASS_FAULT exception table entries") Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Qiuxu Zhuo <qiuxu.zhuo@intel.com> Cc: Ashok Raj <ashok.raj@intel.com> Cc: stable@vger.kernel.org # 4.6+ Cc: Dan Williams <dan.j.williams@intel.com> Cc: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/4cc7c465150a9a48b8b9f45d0b840278e77eb9b5.1527283897.git.tony.luck@intel.com
* | | Kbuild: rename CC_STACKPROTECTOR[_STRONG] config variablesLinus Torvalds2018-06-141-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The changes to automatically test for working stack protector compiler support in the Kconfig files removed the special STACKPROTECTOR_AUTO option that picked the strongest stack protector that the compiler supported. That was all a nice cleanup - it makes no sense to have the AUTO case now that the Kconfig phase can just determine the compiler support directly. HOWEVER. It also meant that doing "make oldconfig" would now _disable_ the strong stackprotector if you had AUTO enabled, because in a legacy config file, the sane stack protector configuration would look like CONFIG_HAVE_CC_STACKPROTECTOR=y # CONFIG_CC_STACKPROTECTOR_NONE is not set # CONFIG_CC_STACKPROTECTOR_REGULAR is not set # CONFIG_CC_STACKPROTECTOR_STRONG is not set CONFIG_CC_STACKPROTECTOR_AUTO=y and when you ran this through "make oldconfig" with the Kbuild changes, it would ask you about the regular CONFIG_CC_STACKPROTECTOR (that had been renamed from CONFIG_CC_STACKPROTECTOR_REGULAR to just CONFIG_CC_STACKPROTECTOR), but it would think that the STRONG version used to be disabled (because it was really enabled by AUTO), and would disable it in the new config, resulting in: CONFIG_HAVE_CC_STACKPROTECTOR=y CONFIG_CC_HAS_STACKPROTECTOR_NONE=y CONFIG_CC_STACKPROTECTOR=y # CONFIG_CC_STACKPROTECTOR_STRONG is not set CONFIG_CC_HAS_SANE_STACKPROTECTOR=y That's dangerously subtle - people could suddenly find themselves with the weaker stack protector setup without even realizing. The solution here is to just rename not just the old RECULAR stack protector option, but also the strong one. This does that by just removing the CC_ prefix entirely for the user choices, because it really is not about the compiler support (the compiler support now instead automatially impacts _visibility_ of the options to users). This results in "make oldconfig" actually asking the user for their choice, so that we don't have any silent subtle security model changes. The end result would generally look like this: CONFIG_HAVE_CC_STACKPROTECTOR=y CONFIG_CC_HAS_STACKPROTECTOR_NONE=y CONFIG_STACKPROTECTOR=y CONFIG_STACKPROTECTOR_STRONG=y CONFIG_CC_HAS_SANE_STACKPROTECTOR=y where the "CC_" versions really are about internal compiler infrastructure, not the user selections. Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | treewide: kzalloc() -> kcalloc()Kees Cook2018-06-123-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The kzalloc() function has a 2-factor argument form, kcalloc(). This patch replaces cases of: kzalloc(a * b, gfp) with: kcalloc(a * b, gfp) as well as handling cases of: kzalloc(a * b * c, gfp) with: kzalloc(array3_size(a, b, c), gfp) as it's slightly less ugly than: kzalloc_array(array_size(a, b), c, gfp) This does, however, attempt to ignore constant size factors like: kzalloc(4 * 1024, gfp) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( kzalloc( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | kzalloc( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( kzalloc( - sizeof(u8) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(__u8) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(char) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(u8) * COUNT + COUNT , ...) | kzalloc( - sizeof(__u8) * COUNT + COUNT , ...) | kzalloc( - sizeof(char) * COUNT + COUNT , ...) | kzalloc( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( - kzalloc + kcalloc ( - sizeof(TYPE) * (COUNT_ID) + COUNT_ID, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * COUNT_ID + COUNT_ID, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * (COUNT_CONST) + COUNT_CONST, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * COUNT_CONST + COUNT_CONST, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (COUNT_ID) + COUNT_ID, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * COUNT_ID + COUNT_ID, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (COUNT_CONST) + COUNT_CONST, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * COUNT_CONST + COUNT_CONST, sizeof(THING) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ - kzalloc + kcalloc ( - SIZE * COUNT + COUNT, SIZE , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( kzalloc( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( kzalloc( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kzalloc( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kzalloc( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( kzalloc( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products, // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( kzalloc(C1 * C2 * C3, ...) | kzalloc( - (E1) * E2 * E3 + array3_size(E1, E2, E3) , ...) | kzalloc( - (E1) * (E2) * E3 + array3_size(E1, E2, E3) , ...) | kzalloc( - (E1) * (E2) * (E3) + array3_size(E1, E2, E3) , ...) | kzalloc( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants, // keeping sizeof() as the second factor argument. @@ expression THING, E1, E2; type TYPE; constant C1, C2, C3; @@ ( kzalloc(sizeof(THING) * C2, ...) | kzalloc(sizeof(TYPE) * C2, ...) | kzalloc(C1 * C2 * C3, ...) | kzalloc(C1 * C2, ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * (E2) + E2, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * E2 + E2, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (E2) + E2, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * E2 + E2, sizeof(THING) , ...) | - kzalloc + kcalloc ( - (E1) * E2 + E1, E2 , ...) | - kzalloc + kcalloc ( - (E1) * (E2) + E1, E2 , ...) | - kzalloc + kcalloc ( - E1 * E2 + E1, E2 , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
* | | Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds2018-06-103-24/+17
|\ \ \ | | |/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 updates and fixes from Thomas Gleixner: - Fix the (late) fallout from the vector management rework causing hlist corruption and irq descriptor reference leaks caused by a missing sanity check. The straight forward fix triggered another long standing issue to surface. The pre rework code hid the issue due to being way slower, but now the chance that user space sees an EBUSY error return when updating irq affinities is way higher, though quite a bunch of userspace tools do not handle it properly despite the fact that EBUSY could be returned for at least 10 years. It turned out that the EBUSY return can be avoided completely by utilizing the existing delayed affinity update mechanism for irq remapped scenarios as well. That's a bit more error handling in the kernel, but avoids fruitless fingerpointing discussions with tool developers. - Decouple PHYSICAL_MASK from AMD SME as its going to be required for the upcoming Intel memory encryption support as well. - Handle legacy device ACPI detection properly for newer platforms - Fix the wrong argument ordering in the vector allocation tracepoint - Simplify the IDT setup code for the APIC=n case - Use the proper string helpers in the MTRR code - Remove a stale unused VDSO source file - Convert the microcode update lock to a raw spinlock as its used in atomic context. * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/intel_rdt: Enable CMT and MBM on new Skylake stepping x86/apic/vector: Print APIC control bits in debugfs genirq/affinity: Defer affinity setting if irq chip is busy x86/platform/uv: Use apic_ack_irq() x86/ioapic: Use apic_ack_irq() irq_remapping: Use apic_ack_irq() x86/apic: Provide apic_ack_irq() genirq/migration: Avoid out of line call if pending is not set genirq/generic_pending: Do not lose pending affinity update x86/apic/vector: Prevent hlist corruption and leaks x86/vector: Fix the args of vector_alloc tracepoint x86/idt: Simplify the idt_setup_apic_and_irq_gates() x86/platform/uv: Remove extra parentheses x86/mm: Decouple dynamic __PHYSICAL_MASK from AMD SME x86: Mark native_set_p4d() as __always_inline x86/microcode: Make the late update update_lock a raw lock for RT x86/mtrr: Convert to use strncpy_from_user() helper x86/mtrr: Convert to use match_string() helper x86/vdso: Remove unused file x86/i8237: Register device based on FADT legacy boot flag
| * | x86/intel_rdt: Enable CMT and MBM on new Skylake steppingTony Luck2018-06-091-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | New stepping of Skylake has fixes for cache occupancy and memory bandwidth monitoring. Update the code to enable these by default on newer steppings. Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: stable@vger.kernel.org # v4.14 Cc: Vikas Shivappa <vikas.shivappa@linux.intel.com> Link: https://lkml.kernel.org/r/20180608160732.9842-1-tony.luck@intel.com
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| *-----. \ Merge branches 'x86/dma', 'x86/microcode', 'x86/mm' and 'x86/vdso' into ↵Ingo Molnar2018-06-042-24/+15
| |\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | x86/urgent Merge these small and simple 1-2 commit branches into the urgent branch. Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | | | * | | x86/mtrr: Convert to use strncpy_from_user() helperAndy Shevchenko2018-05-161-10/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Replace the open coded string fetch from user-space with strncpy_from_user(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Toshi Kani <toshi.kani@hp.com> Link: http://lkml.kernel.org/r/20180515180535.89703-1-andriy.shevchenko@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | | | * | | x86/mtrr: Convert to use match_string() helperAndy Shevchenko2018-05-161-11/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The helper returns index of the matching string in an array. Replace the open coded array lookup with match_string(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Toshi Kani <toshi.kani@hp.com> Link: http://lkml.kernel.org/r/20180515175759.89315-1-andriy.shevchenko@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | | * | | | x86/microcode: Make the late update update_lock a raw lock for RTScott Wood2018-05-271-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | __reload_late() is called from stop_machine context and thus cannot acquire a non-raw spinlock on PREEMPT_RT. Signed-off-by: Scott Wood <swood@redhat.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Ashok Raj <ashok.raj@intel.com> Cc: Clark Williams <williams@redhat.com> Cc: Pei Zhang <pezhang@redhat.com> Cc: x86-ml <x86@kernel.org> Link: http://lkml.kernel.org/r/20180524154420.24455-1-swood@redhat.com
* | | | | | | x86/bugs: Switch the selection of mitigation from CPU vendor to CPU featuresKonrad Rzeszutek Wilk2018-06-061-8/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Both AMD and Intel can have SPEC_CTRL_MSR for SSBD. However AMD also has two more other ways of doing it - which are !SPEC_CTRL MSR ways. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Kees Cook <keescook@chromium.org> Cc: kvm@vger.kernel.org Cc: KarimAllah Ahmed <karahmed@amazon.de> Cc: andrew.cooper3@citrix.com Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Borislav Petkov <bp@suse.de> Cc: David Woodhouse <dwmw@amazon.co.uk> Link: https://lkml.kernel.org/r/20180601145921.9500-4-konrad.wilk@oracle.com
* | | | | | | x86/bugs: Add AMD's SPEC_CTRL MSR usageKonrad Rzeszutek Wilk2018-06-062-5/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The AMD document outlining the SSBD handling 124441_AMD64_SpeculativeStoreBypassDisable_Whitepaper_final.pdf mentions that if CPUID 8000_0008.EBX[24] is set we should be using the SPEC_CTRL MSR (0x48) over the VIRT SPEC_CTRL MSR (0xC001_011f) for speculative store bypass disable. This in effect means we should clear the X86_FEATURE_VIRT_SSBD flag so that we would prefer the SPEC_CTRL MSR. See the document titled: 124441_AMD64_SpeculativeStoreBypassDisable_Whitepaper_final.pdf A copy of this document is available at https://bugzilla.kernel.org/show_bug.cgi?id=199889 Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Tom Lendacky <thomas.lendacky@amd.com> Cc: Janakarajan Natarajan <Janakarajan.Natarajan@amd.com> Cc: kvm@vger.kernel.org Cc: KarimAllah Ahmed <karahmed@amazon.de> Cc: andrew.cooper3@citrix.com Cc: Joerg Roedel <joro@8bytes.org> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Borislav Petkov <bp@suse.de> Cc: David Woodhouse <dwmw@amazon.co.uk> Cc: Kees Cook <keescook@chromium.org> Link: https://lkml.kernel.org/r/20180601145921.9500-3-konrad.wilk@oracle.com
* | | | | | | x86/bugs: Add AMD's variant of SSB_NOKonrad Rzeszutek Wilk2018-06-061-1/+2
| |_|_|_|_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The AMD document outlining the SSBD handling 124441_AMD64_SpeculativeStoreBypassDisable_Whitepaper_final.pdf mentions that the CPUID 8000_0008.EBX[26] will mean that the speculative store bypass disable is no longer needed. A copy of this document is available at: https://bugzilla.kernel.org/show_bug.cgi?id=199889 Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Tom Lendacky <thomas.lendacky@amd.com> Cc: Janakarajan Natarajan <Janakarajan.Natarajan@amd.com> Cc: kvm@vger.kernel.org Cc: andrew.cooper3@citrix.com Cc: Andy Lutomirski <luto@kernel.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Borislav Petkov <bp@suse.de> Cc: David Woodhouse <dwmw@amazon.co.uk> Link: https://lkml.kernel.org/r/20180601145921.9500-2-konrad.wilk@oracle.com
* | | | | | Merge branch 'x86-cache-for-linus' of ↵Linus Torvalds2018-06-045-25/+270
|\ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cache resource controller updates from Thomas Gleixner: "An update for the Intel Resource Director Technolgy (RDT) which adds a feedback driven software controller to runtime adjust the bandwidth allocation MSRs. This makes the allocations more accurate and allows to use bandwidth values in understandable units (MB/s) instead of using percentage based allocations as the original, still available, interface. The software controller can be enabled with a new mount option for the resctrl filesystem" * 'x86-cache-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/intel_rdt/mba_sc: Feedback loop to dynamically update mem bandwidth x86/intel_rdt/mba_sc: Prepare for feedback loop x86/intel_rdt/mba_sc: Add schemata support x86/intel_rdt/mba_sc: Add initialization support x86/intel_rdt/mba_sc: Enable/disable MBA software controller x86/intel_rdt/mba_sc: Documentation for MBA software controller(mba_sc)
| * | | | | | x86/intel_rdt/mba_sc: Feedback loop to dynamically update mem bandwidthVikas Shivappa2018-05-193-3/+128
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | mba_sc is a feedback loop where we periodically read MBM counters and try to restrict the bandwidth below a max value so the below is always true: "current bandwidth(cur_bw) < user specified bandwidth(user_bw)" The frequency of these checks is currently 1s and we just tag along the MBM overflow timer to do the updates. Doing it once in a second also makes the calculation of bandwidth easy. The steps of increase or decrease of bandwidth is the minimum granularity specified by the hardware. Although the MBA's goal is to restrict the bandwidth below a maximum, there may be a need to even increase the bandwidth. Since MBA controls the L2 external bandwidth where as MBM measures the L3 external bandwidth, we may end up restricting some rdtgroups unnecessarily. This may happen in the sequence where rdtgroup (set of jobs) had high "L3 <-> memory traffic" in initial phases -> mba_sc kicks in and reduced bandwidth percentage values -> but after some it has mostly "L2 <-> L3" traffic. In this scenario mba_sc increases the bandwidth percentage when there is lesser memory traffic. Signed-off-by: Vikas Shivappa <vikas.shivappa@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: ravi.v.shankar@intel.com Cc: tony.luck@intel.com Cc: fenghua.yu@intel.com Cc: vikas.shivappa@intel.com Cc: ak@linux.intel.com Cc: hpa@zytor.com Link: https://lkml.kernel.org/r/1524263781-14267-7-git-send-email-vikas.shivappa@linux.intel.com
| * | | | | | x86/intel_rdt/mba_sc: Prepare for feedback loopVikas Shivappa2018-05-192-6/+48
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is a preparatory patch for the mba feedback loop. Add support to measure the "bandwidth in MBps" and the "delta bandwidth". Measure it by reading the MBM IA32_QM_CTR MSRs and calculating the amount of "bytes" moved. There is no user space interface for this and will only be used by the feedback loop patch. Signed-off-by: Vikas Shivappa <vikas.shivappa@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: ravi.v.shankar@intel.com Cc: tony.luck@intel.com Cc: fenghua.yu@intel.com Cc: vikas.shivappa@intel.com Cc: ak@linux.intel.com Cc: hpa@zytor.com Link: https://lkml.kernel.org/r/1524263781-14267-6-git-send-email-vikas.shivappa@linux.intel.com
| * | | | | | x86/intel_rdt/mba_sc: Add schemata supportVikas Shivappa2018-05-192-6/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently when user updates the "schemata" with new MBA percentage values, kernel writes the corresponding bandwidth percentage values to the IA32_MBA_THRTL_MSR. When MBA is expressed in MBps, the schemata format is changed to have the per package memory bandwidth in MBps instead of being specified in percentage. Do not write the IA32_MBA_THRTL_MSRs when the schemata is updated as that is handled separately. Signed-off-by: Vikas Shivappa <vikas.shivappa@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: ravi.v.shankar@intel.com Cc: tony.luck@intel.com Cc: fenghua.yu@intel.com Cc: vikas.shivappa@intel.com Cc: ak@linux.intel.com Cc: hpa@zytor.com Link: https://lkml.kernel.org/r/1524263781-14267-5-git-send-email-vikas.shivappa@linux.intel.com
| * | | | | | x86/intel_rdt/mba_sc: Add initialization supportVikas Shivappa2018-05-193-10/+33
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When MBA software controller is enabled, a per domain storage is required for user specified bandwidth in "MBps" and the "percentage" values which are programmed into the IA32_MBA_THRTL_MSR. Add support for these data structures and initialization. The MBA percentage values have a default max value of 100 but however the max value in MBps is not available from the hardware so it's set to U32_MAX. This simply says that the control group can use all bandwidth by default but does not say what is the actual max bandwidth available. The actual bandwidth that is available may depend on lot of factors like QPI link, number of memory channels, memory channel frequency, its width and memory speed, how many channels are configured and also if memory interleaving is enabled. So there is no way to determine the maximum at runtime reliably. Signed-off-by: Vikas Shivappa <vikas.shivappa@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: ravi.v.shankar@intel.com Cc: tony.luck@intel.com Cc: fenghua.yu@intel.com Cc: vikas.shivappa@intel.com Cc: ak@linux.intel.com Cc: hpa@zytor.com Link: https://lkml.kernel.org/r/1524263781-14267-4-git-send-email-vikas.shivappa@linux.intel.com
| * | | | | | x86/intel_rdt/mba_sc: Enable/disable MBA software controllerVikas Shivappa2018-05-193-0/+41
| | |_|_|/ / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently user does memory bandwidth allocation(MBA) by specifying the bandwidth in percentage via the resctrl schemata file: "/sys/fs/resctrl/schemata" Add a new mount option "mba_MBps" to enable the user to specify MBA in MBps: $mount -t resctrl resctrl [-o cdp[,cdpl2][mba_MBps]] /sys/fs/resctrl Signed-off-by: Vikas Shivappa <vikas.shivappa@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: ravi.v.shankar@intel.com Cc: tony.luck@intel.com Cc: fenghua.yu@intel.com Cc: vikas.shivappa@intel.com Cc: ak@linux.intel.com Cc: hpa@zytor.com Link: https://lkml.kernel.org/r/1524263781-14267-3-git-send-email-vikas.shivappa@linux.intel.com
* | | | | | Merge branch 'ras-core-for-linus' of ↵Linus Torvalds2018-06-043-9/+26
|\ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 RAS updates from Thomas Gleixner: - Fix a stack out of bounds write in the MCE error injection code. - Avoid IPIs during CPU hotplug to read the MCx_MISC block address from a remote CPU. That's fragile and pointless because the block addresses are the same on all CPUs. So they can be read once and local. - Add support for MCE broadcasting on newer VIA Centaur CPUs. * 'ras-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/MCE/AMD: Read MCx_MISC block addresses on any CPU x86/MCE: Fix stack out-of-bounds write in mce-inject.c: Flags_read() x86/MCE: Enable MCE broadcasting on new Centaur CPUs
| * | | | | | x86/MCE/AMD: Read MCx_MISC block addresses on any CPUBorislav Petkov2018-05-191-8/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We used rdmsr_safe_on_cpu() to make sure we're reading the proper CPU's MISC block addresses. However, that caused trouble with CPU hotplug due to the _on_cpu() helper issuing an IPI while IRQs are disabled. But we don't have to do that: the block addresses are the same on any CPU so we can read them on any CPU. (What practically happens is, we read them on the BSP and cache them, and for later reads, we service them from the cache). Suggested-by: Yazen Ghannam <Yazen.Ghannam@amd.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | | | Merge branch 'ras/urgent' into ras/coreThomas Gleixner2018-05-192-16/+19
| |\ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | Pick up urgent fix as pending patch depends on it.
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