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* Merge branch 'x86-smap-for-linus' of ↵Linus Torvalds2013-09-041-3/+3
|\ | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 SMAP fixes from Ingo Molnar: "Fixes for Intel SMAP support, to fix SIGSEGVs during bootup" * 'x86-smap-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: Introduce [compat_]save_altstack_ex() to unbreak x86 SMAP x86, smap: Handle csum_partial_copy_*_user()
| * Introduce [compat_]save_altstack_ex() to unbreak x86 SMAPAl Viro2013-09-011-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For performance reasons, when SMAP is in use, SMAP is left open for an entire put_user_try { ... } put_user_catch(); block, however, calling __put_user() in the middle of that block will close SMAP as the STAC..CLAC constructs intentionally do not nest. Furthermore, using __put_user() rather than put_user_ex() here is bad for performance. Thus, introduce new [compat_]save_altstack_ex() helpers that replace __[compat_]save_altstack() for x86, being currently the only architecture which supports put_user_try { ... } put_user_catch(). Reported-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: <stable@vger.kernel.org> # v3.8+ Link: http://lkml.kernel.org/n/tip-es5p6y64if71k8p5u08agv9n@git.kernel.org
* | x86, asmlinkage: Make several variables used from assembler/linker script ↵Andi Kleen2013-08-061-1/+1
| | | | | | | | | | | | | | | | | | | | visible Plus one function, load_gs_index(). Signed-off-by: Andi Kleen <ak@linux.intel.com> Link: http://lkml.kernel.org/r/1375740170-7446-10-git-send-email-andi@firstfloor.org Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* | x86, asmlinkage: Make various syscalls asmlinkageAndi Kleen2013-08-061-2/+2
|/ | | | | | | | | | FWIW I suspect sys_rt_sigreturn/sys_sigreturn should use standard SYSCALL wrappers. But I didn't do that change in this patch. Signed-off-by: Andi Kleen <ak@linux.intel.com> Link: http://lkml.kernel.org/r/1375740170-7446-7-git-send-email-andi@firstfloor.org Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* x86/signals: Merge EFLAGS bit clearing into a single statementJiri Olsa2013-05-281-7/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | Merging EFLAGS bit clearing into a single statement, to ensure EFLAGS bits are being cleared in a single instruction. Signed-off-by: Jiri Olsa <jolsa@redhat.com> Tested-by: Oleg Nesterov <oleg@redhat.com> Reviewed-by: Frederic Weisbecker <fweisbec@gmail.com> Originally-Reported-by: Vince Weaver <vincent.weaver@maine.edu> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Cc: Ingo Molnar <mingo@elte.hu> Cc: Paul Mackerras <paulus@samba.org> Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: Stephane Eranian <eranian@google.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1367421944-19082-4-git-send-email-jolsa@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* x86/signals: Clear RF EFLAGS bit for signal handlerJiri Olsa2013-05-281-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Clearing RF EFLAGS bit for signal handler. The reason is that this flag is set by debug exception code to prevent the recursive exception entry. Leaving it set for signal handler might prevent debug exception of the signal handler itself. Signed-off-by: Jiri Olsa <jolsa@redhat.com> Tested-by: Oleg Nesterov <oleg@redhat.com> Reviewed-by: Frederic Weisbecker <fweisbec@gmail.com> Originally-Reported-by: Vince Weaver <vincent.weaver@maine.edu> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Cc: Ingo Molnar <mingo@elte.hu> Cc: Paul Mackerras <paulus@samba.org> Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: Stephane Eranian <eranian@google.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1367421944-19082-3-git-send-email-jolsa@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* x86/signals: Propagate RF EFLAGS bit through the signal restore callJiri Olsa2013-05-281-6/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | While porting Vince's perf overflow tests I found perf event breakpoint overflow does not work properly. I found the x86 RF EFLAG bit not being set when returning from debug exception after triggering signal handler. Which is exactly what you get when you set perf breakpoint overflow SIGIO handler. This patch and the next two patches fix the underlying bugs. This patch adds the RF EFLAGS bit to be restored on return from signal from the original register context before the signal was entered. This will prevent the RF flag to disappear when returning from exception due to the signal handler being executed. Signed-off-by: Jiri Olsa <jolsa@redhat.com> Tested-by: Oleg Nesterov <oleg@redhat.com> Reviewed-by: Frederic Weisbecker <fweisbec@gmail.com> Originally-Reported-by: Vince Weaver <vincent.weaver@maine.edu> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Cc: Ingo Molnar <mingo@elte.hu> Cc: Paul Mackerras <paulus@samba.org> Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: Stephane Eranian <eranian@google.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1367421944-19082-2-git-send-email-jolsa@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* x86: convert to ksignalAl Viro2013-02-141-63/+54
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* x86: switch to generic old sigactionAl Viro2013-02-031-47/+0
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* x86,um: switch to generic old sigsuspend()Al Viro2013-02-031-11/+0
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* x86: get rid of pt_regs argument in sigreturn variantsAl Viro2013-02-031-3/+6
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* Merge branch 'for-linus' of ↵Linus Torvalds2012-12-201-24/+5
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal Pull signal handling cleanups from Al Viro: "sigaltstack infrastructure + conversion for x86, alpha and um, COMPAT_SYSCALL_DEFINE infrastructure. Note that there are several conflicts between "unify SS_ONSTACK/SS_DISABLE definitions" and UAPI patches in mainline; resolution is trivial - just remove definitions of SS_ONSTACK and SS_DISABLED from arch/*/uapi/asm/signal.h; they are all identical and include/uapi/linux/signal.h contains the unified variant." Fixed up conflicts as per Al. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: alpha: switch to generic sigaltstack new helpers: __save_altstack/__compat_save_altstack, switch x86 and um to those generic compat_sys_sigaltstack() introduce generic sys_sigaltstack(), switch x86 and um to it new helper: compat_user_stack_pointer() new helper: restore_altstack() unify SS_ONSTACK/SS_DISABLE definitions new helper: current_user_stack_pointer() missing user_stack_pointer() instances Bury the conditionals from kernel_thread/kernel_execve series COMPAT_SYSCALL_DEFINE: infrastructure
| * new helpers: __save_altstack/__compat_save_altstack, switch x86 and um to thoseAl Viro2012-12-191-14/+4
| | | | | | | | | | | | note that they are relying on access_ok() already checked by caller. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| * generic compat_sys_sigaltstack()Al Viro2012-12-191-3/+1
| | | | | | | | | | | | Again, conditional on CONFIG_GENERIC_SIGALTSTACK Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| * introduce generic sys_sigaltstack(), switch x86 and um to itAl Viro2012-12-191-7/+0
| | | | | | | | | | | | | | Conditional on CONFIG_GENERIC_SIGALTSTACK; architectures that do not select it are completely unaffected Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | Merge branch 'rcu/next' of ↵Ingo Molnar2012-12-031-2/+3
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu Conflicts: arch/x86/kernel/ptrace.c Pull the latest RCU tree from Paul E. McKenney: " The major features of this series are: 1. A first version of no-callbacks CPUs. This version prohibits offlining CPU 0, but only when enabled via CONFIG_RCU_NOCB_CPU=y. Relaxing this constraint is in progress, but not yet ready for prime time. These commits were posted to LKML at https://lkml.org/lkml/2012/10/30/724, and are at branch rcu/nocb. 2. Changes to SRCU that allows statically initialized srcu_struct structures. These commits were posted to LKML at https://lkml.org/lkml/2012/10/30/296, and are at branch rcu/srcu. 3. Restructuring of RCU's debugfs output. These commits were posted to LKML at https://lkml.org/lkml/2012/10/30/341, and are at branch rcu/tracing. 4. Additional CPU-hotplug/RCU improvements, posted to LKML at https://lkml.org/lkml/2012/10/30/327, and are at branch rcu/hotplug. Note that the commit eliminating __stop_machine() was judged to be too-high of risk, so is deferred to 3.9. 5. Changes to RCU's idle interface, most notably a new module parameter that redirects normal grace-period operations to their expedited equivalents. These were posted to LKML at https://lkml.org/lkml/2012/10/30/739, and are at branch rcu/idle. 6. Additional diagnostics for RCU's CPU stall warning facility, posted to LKML at https://lkml.org/lkml/2012/10/30/315, and are at branch rcu/stall. The most notable change reduces the default RCU CPU stall-warning time from 60 seconds to 21 seconds, so that it once again happens sooner than the softlockup timeout. 7. Documentation updates, which were posted to LKML at https://lkml.org/lkml/2012/10/30/280, and are at branch rcu/doc. A couple of late-breaking changes were posted at https://lkml.org/lkml/2012/11/16/634 and https://lkml.org/lkml/2012/11/16/547. 8. Miscellaneous fixes, which were posted to LKML at https://lkml.org/lkml/2012/10/30/309, along with a late-breaking change posted at Fri, 16 Nov 2012 11:26:25 -0800 with message-ID <20121116192625.GA447@linux.vnet.ibm.com>, but which lkml.org seems to have missed. These are at branch rcu/fixes. 9. Finally, a fix for an lockdep-RCU splat was posted to LKML at https://lkml.org/lkml/2012/11/7/486. This is at rcu/next. " Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * context_tracking: New context tracking susbsystemFrederic Weisbecker2012-11-301-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Create a new subsystem that probes on kernel boundaries to keep track of the transitions between level contexts with two basic initial contexts: user or kernel. This is an abstraction of some RCU code that use such tracking to implement its userspace extended quiescent state. We need to pull this up from RCU into this new level of indirection because this tracking is also going to be used to implement an "on demand" generic virtual cputime accounting. A necessary step to shutdown the tick while still accounting the cputime. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Gilad Ben-Yossef <gilad@benyossef.com> Reviewed-by: Steven Rostedt <rostedt@goodmis.org> [ paulmck: fix whitespace error and email address. ] Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* | Merge branch 'uprobes/core' of ↵Ingo Molnar2012-10-211-3/+1
|\ \ | |/ |/| | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/oleg/misc into perf/urgent Pull various uprobes bugfixes from Oleg Nesterov - mostly race and failure path fixes. Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * uprobes: Move clear_thread_flag(TIF_UPROBE) to uprobe_notify_resume()Oleg Nesterov2012-09-291-3/+1
| | | | | | | | | | | | | | | | Move clear_thread_flag(TIF_UPROBE) from do_notify_resume() to uprobe_notify_resume() for !CONFIG_UPROBES case. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
* | Merge branch 'for-linus' of ↵Linus Torvalds2012-10-101-4/+0
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal Pull generic execve() changes from Al Viro: "This introduces the generic kernel_thread() and kernel_execve() functions, and switches x86, arm, alpha, um and s390 over to them." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: (26 commits) s390: convert to generic kernel_execve() s390: switch to generic kernel_thread() s390: fold kernel_thread_helper() into ret_from_fork() s390: fold execve_tail() into start_thread(), convert to generic sys_execve() um: switch to generic kernel_thread() x86, um/x86: switch to generic sys_execve and kernel_execve x86: split ret_from_fork alpha: introduce ret_from_kernel_execve(), switch to generic kernel_execve() alpha: switch to generic kernel_thread() alpha: switch to generic sys_execve() arm: get rid of execve wrapper, switch to generic execve() implementation arm: optimized current_pt_regs() arm: introduce ret_from_kernel_execve(), switch to generic kernel_execve() arm: split ret_from_fork, simplify kernel_thread() [based on patch by rmk] generic sys_execve() generic kernel_execve() new helper: current_pt_regs() preparation for generic kernel_thread() um: kill thread->forking um: let signal_delivered() do SIGTRAP on singlestepping into handler ...
| * | x86: get rid of TIF_IRET hackeryAl Viro2012-09-201-4/+0
| |/ | | | | | | | | | | | | | | | | | | TIF_NOTIFY_RESUME will work in precisely the same way; all that is achieved by TIF_IRET is appearing that there's some work to be done, so we end up on the iret exit path. Just use NOTIFY_RESUME. And for execve() do that in 32bit start_thread(), not sys_execve() itself. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | Merge branch 'x86-smap-for-linus' of ↵Linus Torvalds2012-10-011-10/+14
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86/smap support from Ingo Molnar: "This adds support for the SMAP (Supervisor Mode Access Prevention) CPU feature on Intel CPUs: a hardware feature that prevents unintended user-space data access from kernel privileged code. It's turned on automatically when possible. This, in combination with SMEP, makes it even harder to exploit kernel bugs such as NULL pointer dereferences." Fix up trivial conflict in arch/x86/kernel/entry_64.S due to newly added includes right next to each other. * 'x86-smap-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, smep, smap: Make the switching functions one-way x86, suspend: On wakeup always initialize cr4 and EFER x86-32: Start out eflags and cr4 clean x86, smap: Do not abuse the [f][x]rstor_checking() functions for user space x86-32, smap: Add STAC/CLAC instructions to 32-bit kernel entry x86, smap: Reduce the SMAP overhead for signal handling x86, smap: A page fault due to SMAP is an oops x86, smap: Turn on Supervisor Mode Access Prevention x86, smap: Add STAC and CLAC instructions to control user space access x86, uaccess: Merge prototypes for clear_user/__clear_user x86, smap: Add a header file with macros for STAC/CLAC x86, alternative: Add header guards to <asm/alternative-asm.h> x86, alternative: Use .pushsection/.popsection x86, smap: Add CR4 bit for SMAP x86-32, mm: The WP test should be done on a kernel page
| * \ Merge branch 'x86/fpu' into x86/smapH. Peter Anvin2012-09-211-124/+91
| |\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Reason for merge: x86/fpu changed the structure of some of the code that x86/smap changes; mostly fpu-internal.h but also minor changes to the signal code. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Resolved Conflicts: arch/x86/ia32/ia32_signal.c arch/x86/include/asm/fpu-internal.h arch/x86/kernel/signal.c
| * | | x86, smap: Reduce the SMAP overhead for signal handlingH. Peter Anvin2012-09-211-10/+14
| | |/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Signal handling contains a bunch of accesses to individual user space items, which causes an excessive number of STAC and CLAC instructions. Instead, let get/put_user_try ... get/put_user_catch() contain the STAC and CLAC instructions. This means that get/put_user_try no longer nests, and furthermore that it is no longer legal to use user space access functions other than __get/put_user_ex() inside those blocks. However, these macros are x86-specific anyway and are only used in the signal-handling paths; a simple reordering of moving the larger subroutine calls out of the try...catch blocks resolves that problem. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/r/1348256595-29119-12-git-send-email-hpa@linux.intel.com
* | | Merge branch 'x86-fpu-for-linus' of ↵Linus Torvalds2012-10-011-122/+89
|\ \ \ | | |/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86/fpu update from Ingo Molnar: "The biggest change is the addition of the non-lazy (eager) FPU saving support model and enabling it on CPUs with optimized xsaveopt/xrstor FPU state saving instructions. There are also various Sparse fixes" Fix up trivial add-add conflict in arch/x86/kernel/traps.c * 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, kvm: fix kvm's usage of kernel_fpu_begin/end() x86, fpu: remove cpu_has_xmm check in the fx_finit() x86, fpu: make eagerfpu= boot param tri-state x86, fpu: enable eagerfpu by default for xsaveopt x86, fpu: decouple non-lazy/eager fpu restore from xsave x86, fpu: use non-lazy fpu restore for processors supporting xsave lguest, x86: handle guest TS bit for lazy/non-lazy fpu host models x86, fpu: always use kernel_fpu_begin/end() for in-kernel FPU usage x86, kvm: use kernel_fpu_begin/end() in kvm_load/put_guest_fpu() x86, fpu: remove unnecessary user_fpu_end() in save_xstate_sig() x86, fpu: drop_fpu() before restoring new state from sigframe x86, fpu: Unify signal handling code paths for x86 and x86_64 kernels x86, fpu: Consolidate inline asm routines for saving/restoring fpu state x86, signal: Cleanup ifdefs and is_ia32, is_x32
| * | x86, fpu: Unify signal handling code paths for x86 and x86_64 kernelsSuresh Siddha2012-09-181-7/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently for x86 and x86_32 binaries, fpstate in the user sigframe is copied to/from the fpstate in the task struct. And in the case of signal delivery for x86_64 binaries, if the fpstate is live in the CPU registers, then the live state is copied directly to the user sigframe. Otherwise fpstate in the task struct is copied to the user sigframe. During restore, fpstate in the user sigframe is restored directly to the live CPU registers. Historically, different code paths led to different bugs. For example, x86_64 code path was not preemption safe till recently. Also there is lot of code duplication for support of new features like xsave etc. Unify signal handling code paths for x86 and x86_64 kernels. New strategy is as follows: Signal delivery: Both for 32/64-bit frames, align the core math frame area to 64bytes as needed by xsave (this where the main fpu/extended state gets copied to and excludes the legacy compatibility fsave header for the 32-bit [f]xsave frames). If the state is live, copy the register state directly to the user frame. If not live, copy the state in the thread struct to the user frame. And for 32-bit [f]xsave frames, construct the fsave header separately before the actual [f]xsave area. Signal return: As the 32-bit frames with [f]xstate has an additional 'fsave' header, copy everything back from the user sigframe to the fpstate in the task structure and reconstruct the fxstate from the 'fsave' header (Also user passed pointers may not be correctly aligned for any attempt to directly restore any partial state). At the next fpstate usage, everything will be restored to the live CPU registers. For all the 64-bit frames and the 32-bit fsave frame, restore the state from the user sigframe directly to the live CPU registers. 64-bit signals always restored the math frame directly, so we can expect the math frame pointer to be correctly aligned. For 32-bit fsave frames, there are no alignment requirements, so we can restore the state directly. "lat_sig catch" microbenchmark numbers (for x86, x86_64, x86_32 binaries) are with in the noise range with this change. Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Link: http://lkml.kernel.org/r/1343171129-2747-4-git-send-email-suresh.b.siddha@intel.com [ Merged in compilation fix ] Link: http://lkml.kernel.org/r/1344544736.8326.17.camel@sbsiddha-desk.sc.intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
| * | x86, signal: Cleanup ifdefs and is_ia32, is_x32Suresh Siddha2012-09-181-115/+81
| |/ | | | | | | | | | | | | | | | | | | | | | | Use config_enabled() to cleanup the definitions of is_ia32/is_x32. Move the function prototypes to the header file to cleanup ifdefs, and move the x32_setup_rt_frame() code around. Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Link: http://lkml.kernel.org/r/1343171129-2747-2-git-send-email-suresh.b.siddha@intel.com Merged in compilation fix from, Link: http://lkml.kernel.org/r/1344544736.8326.17.camel@sbsiddha-desk.sc.intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* | x86: Exit RCU extended QS on notify resumeFrederic Weisbecker2012-09-261-0/+4
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | do_notify_resume() may be called on irq or exception exit. But at that time the exception has already called rcu_user_enter() and the irq has already called rcu_irq_exit(). Since it can use RCU read side critical section, we must call rcu_user_exit() before doing anything there. Then we must call back rcu_user_enter() after this function because we know we are going to userspace from there. This complete support for userspace RCU extended quiescent state in x86-64. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Alessio Igor Bogani <abogani@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Avi Kivity <avi@redhat.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Christoph Lameter <cl@linux.com> Cc: Geoff Levand <geoff@infradead.org> Cc: Gilad Ben Yossef <gilad@benyossef.com> Cc: Hakan Akkan <hakanakkan@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Kevin Hilman <khilman@ti.com> Cc: Max Krasnyansky <maxk@qualcomm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephen Hemminger <shemminger@vyatta.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sven-Thorsten Dietrich <thebigcorporation@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
* x86/debug: Add KERN_<LEVEL> to bare printks, convert printks to pr_<level>Joe Perches2012-06-061-1/+4
| | | | | | | | | | | | | | | | | | | Use a more current logging style: - Bare printks should have a KERN_<LEVEL> for consistency's sake - Add pr_fmt where appropriate - Neaten some macro definitions - Convert some Ok output to OK - Use "%s: ", __func__ in pr_fmt for summit - Convert some printks to pr_<level> Message output is not identical in all cases. Signed-off-by: Joe Perches <joe@perches.com> Cc: levinsasha928@gmail.com Link: http://lkml.kernel.org/r/1337655007.24226.10.camel@joe2Laptop [ merged two similar patches, tidied up the changelog ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
* x86: get rid of calling do_notify_resume() when returning to kernel modeAl Viro2012-06-011-10/+0
| | | | | | | | | | | | | | | | | | If we end up calling do_notify_resume() with !user_mode(refs), it does nothing (do_signal() explicitly bails out and we can't get there with TIF_NOTIFY_RESUME in such situations). Then we jump to resume_userspace_sig, which rechecks the same thing and bails out to resume_kernel, thus breaking the loop. It's easier and cheaper to check *before* calling do_notify_resume() and bail out to resume_kernel immediately. And kill the check in do_signal()... Note that on amd64 we can't get there with !user_mode() at all - asm glue takes care of that. Acked-and-reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* new helper: signal_delivered()Al Viro2012-06-011-4/+2
| | | | | | | | | | | | | | Does block_sigmask() + tracehook_signal_handler(); called when sigframe has been successfully built. All architectures converted to it; block_sigmask() itself is gone now (merged into this one). I'm still not too happy with the signature, but that's a separate story (IMO we need a structure that would contain signal number + siginfo + k_sigaction, so that get_signal_to_deliver() would fill one, signal_delivered(), handle_signal() and probably setup...frame() - take one). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* most of set_current_blocked() callers want SIGKILL/SIGSTOP removed from setAl Viro2012-06-011-3/+0
| | | | | | | | Only 3 out of 63 do not. Renamed the current variant to __set_current_blocked(), added set_current_blocked() that will exclude unblockable signals, switched open-coded instances to it. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* pull clearing RESTORE_SIGMASK into block_sigmask()Al Viro2012-06-011-22/+9
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* new helper: sigmask_to_save()Al Viro2012-06-011-4/+1
| | | | | | | replace boilerplate "should we use ->saved_sigmask or ->blocked?" with calls of obvious inlined helper... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* new helper: restore_saved_sigmask()Al Viro2012-06-011-4/+1
| | | | | | | | | first fruits of ..._restore_sigmask() helpers: now we can take boilerplate "signal didn't have a handler, clear RESTORE_SIGMASK and restore the blocked mask from ->saved_mask" into a common helper. Open-coded instances switched... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* Merge branch 'for-linus' of ↵Linus Torvalds2012-05-311-2/+0
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal Pull second pile of signal handling patches from Al Viro: "This one is just task_work_add() series + remaining prereqs for it. There probably will be another pull request from that tree this cycle - at least for helpers, to get them out of the way for per-arch fixes remaining in the tree." Fix trivial conflict in kernel/irq/manage.c: the merge of Andrew's pile had brought in commit 97fd75b7b8e0 ("kernel/irq/manage.c: use the pr_foo() infrastructure to prefix printks") which changed one of the pr_err() calls that this merge moves around. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: keys: kill task_struct->replacement_session_keyring keys: kill the dummy key_replace_session_keyring() keys: change keyctl_session_to_parent() to use task_work_add() genirq: reimplement exit_irq_thread() hook via task_work_add() task_work_add: generic process-context callbacks avr32: missed _TIF_NOTIFY_RESUME on one of do_notify_resume callers parisc: need to check NOTIFY_RESUME when exiting from syscall move key_repace_session_keyring() into tracehook_notify_resume() TIF_NOTIFY_RESUME is defined on all targets now
| * move key_repace_session_keyring() into tracehook_notify_resume()Al Viro2012-05-231-2/+0
| | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | Merge branch 'perf-uprobes-for-linus' of ↵Linus Torvalds2012-05-241-0/+6
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull user-space probe instrumentation from Ingo Molnar: "The uprobes code originates from SystemTap and has been used for years in Fedora and RHEL kernels. This version is much rewritten, reviews from PeterZ, Oleg and myself shaped the end result. This tree includes uprobes support in 'perf probe' - but SystemTap (and other tools) can take advantage of user probe points as well. Sample usage of uprobes via perf, for example to profile malloc() calls without modifying user-space binaries. First boot a new kernel with CONFIG_UPROBE_EVENT=y enabled. If you don't know which function you want to probe you can pick one from 'perf top' or can get a list all functions that can be probed within libc (binaries can be specified as well): $ perf probe -F -x /lib/libc.so.6 To probe libc's malloc(): $ perf probe -x /lib64/libc.so.6 malloc Added new event: probe_libc:malloc (on 0x7eac0) You can now use it in all perf tools, such as: perf record -e probe_libc:malloc -aR sleep 1 Make use of it to create a call graph (as the flat profile is going to look very boring): $ perf record -e probe_libc:malloc -gR make [ perf record: Woken up 173 times to write data ] [ perf record: Captured and wrote 44.190 MB perf.data (~1930712 $ perf report | less 32.03% git libc-2.15.so [.] malloc | --- malloc 29.49% cc1 libc-2.15.so [.] malloc | --- malloc | |--0.95%-- 0x208eb1000000000 | |--0.63%-- htab_traverse_noresize 11.04% as libc-2.15.so [.] malloc | --- malloc | 7.15% ld libc-2.15.so [.] malloc | --- malloc | 5.07% sh libc-2.15.so [.] malloc | --- malloc | 4.99% python-config libc-2.15.so [.] malloc | --- malloc | 4.54% make libc-2.15.so [.] malloc | --- malloc | |--7.34%-- glob | | | |--93.18%-- 0x41588f | | | --6.82%-- glob | 0x41588f ... Or: $ perf report -g flat | less # Overhead Command Shared Object Symbol # ........ ............. ............. .......... # 32.03% git libc-2.15.so [.] malloc 27.19% malloc 29.49% cc1 libc-2.15.so [.] malloc 24.77% malloc 11.04% as libc-2.15.so [.] malloc 11.02% malloc 7.15% ld libc-2.15.so [.] malloc 6.57% malloc ... The core uprobes design is fairly straightforward: uprobes probe points register themselves at (inode:offset) addresses of libraries/binaries, after which all existing (or new) vmas that map that address will have a software breakpoint injected at that address. vmas are COW-ed to preserve original content. The probe points are kept in an rbtree. If user-space executes the probed inode:offset instruction address then an event is generated which can be recovered from the regular perf event channels and mmap-ed ring-buffer. Multiple probes at the same address are supported, they create a dynamic callback list of event consumers. The basic model is further complicated by the XOL speedup: the original instruction that is probed is copied (in an architecture specific fashion) and executed out of line when the probe triggers. The XOL area is a single vma per process, with a fixed number of entries (which limits probe execution parallelism). The API: uprobes are installed/removed via /sys/kernel/debug/tracing/uprobe_events, the API is integrated to align with the kprobes interface as much as possible, but is separate to it. Injecting a probe point is privileged operation, which can be relaxed by setting perf_paranoid to -1. You can use multiple probes as well and mix them with kprobes and regular PMU events or tracepoints, when instrumenting a task." Fix up trivial conflicts in mm/memory.c due to previous cleanup of unmap_single_vma(). * 'perf-uprobes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (21 commits) perf probe: Detect probe target when m/x options are absent perf probe: Provide perf interface for uprobes tracing: Fix kconfig warning due to a typo tracing: Provide trace events interface for uprobes tracing: Extract out common code for kprobes/uprobes trace events tracing: Modify is_delete, is_return from int to bool uprobes/core: Decrement uprobe count before the pages are unmapped uprobes/core: Make background page replacement logic account for rss_stat counters uprobes/core: Optimize probe hits with the help of a counter uprobes/core: Allocate XOL slots for uprobes use uprobes/core: Handle breakpoint and singlestep exceptions uprobes/core: Rename bkpt to swbp uprobes/core: Make order of function parameters consistent across functions uprobes/core: Make macro names consistent uprobes: Update copyright notices uprobes/core: Move insn to arch specific structure uprobes/core: Remove uprobe_opcode_sz uprobes/core: Make instruction tables volatile uprobes: Move to kernel/events/ uprobes/core: Clean up, refactor and improve the code ...
| * Merge branch 'perf/core' into perf/uprobesIngo Molnar2012-04-141-0/+1
| |\ | | | | | | | | | | | | | | | | | | | | | Merge in latest upstream (and the latest perf development tree), to prepare for tooling changes, and also to pick up v3.4 MM changes that the uprobes code needs to take care of. Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | uprobes/core: Handle breakpoint and singlestep exceptionsSrikar Dronamraju2012-03-141-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Uprobes uses exception notifiers to get to know if a thread hit a breakpoint or a singlestep exception. When a thread hits a uprobe or is singlestepping post a uprobe hit, the uprobe exception notifier sets its TIF_UPROBE bit, which will then be checked on its return to userspace path (do_notify_resume() ->uprobe_notify_resume()), where the consumers handlers are run (in task context) based on the defined filters. Uprobe hits are thread specific and hence we need to maintain information about if a task hit a uprobe, what uprobe was hit, the slot where the original instruction was copied for xol so that it can be singlestepped with appropriate fixups. In some cases, special care is needed for instructions that are executed out of line (xol). These are architecture specific artefacts, such as handling RIP relative instructions on x86_64. Since the instruction at which the uprobe was inserted is executed out of line, architecture specific fixups are added so that the thread continues normal execution in the presence of a uprobe. Postpone the signals until we execute the probed insn. post_xol() path does a recalc_sigpending() before return to user-mode, this ensures the signal can't be lost. Uprobes relies on DIE_DEBUG notification to notify if a singlestep is complete. Adds x86 specific uprobe exception notifiers and appropriate hooks needed to determine a uprobe hit and subsequent post processing. Add requisite x86 fixups for xol for uprobes. Specific cases needing fixups include relative jumps (x86_64), calls, etc. Where possible, we check and skip singlestepping the breakpointed instructions. For now we skip single byte as well as few multibyte nop instructions. However this can be extended to other instructions too. Credits to Oleg Nesterov for suggestions/patches related to signal, breakpoint, singlestep handling code. Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Jim Keniston <jkenisto@linux.vnet.ibm.com> Cc: Linux-mm <linux-mm@kvack.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Christoph Hellwig <hch@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20120313180011.29771.89027.sendpatchset@srdronam.in.ibm.com [ Performed various cleanliness edits ] Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | | new helper: sigsuspend()Al Viro2012-05-211-11/+1
| |/ |/| | | | | | | | | | | | | | | guts of saved_sigmask-based sigsuspend/rt_sigsuspend. Takes kernel sigset_t *. Open-coded instances replaced with calling it. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | Merge branch 'x86-cleanups-for-linus' of ↵Linus Torvalds2012-03-291-1/+1
|\ \ | |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cleanups from Peter Anvin: "The biggest textual change is the cleanup to use symbolic constants for x86 trap values. The only *functional* change and the reason for the x86/x32 dependency is the move of is_ia32_task() into <asm/thread_info.h> so that it can be used in other code that needs to understand if a system call comes from the compat entry point (and therefore uses i386 system call numbers) or not. One intended user for that is the BPF system call filter. Moving it out of <asm/compat.h> means we can define it unconditionally, returning always true on i386." * 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86: Move is_ia32_task to asm/thread_info.h from asm/compat.h x86: Rename trap_no to trap_nr in thread_struct x86: Use enum instead of literals for trap values
| * x86: Rename trap_no to trap_nr in thread_structSrikar Dronamraju2012-03-131-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There are precedences of trap number being referred to as trap_nr. However thread struct refers trap number as trap_no. Change it to trap_nr. Also use enum instead of left-over literals for trap values. This is pure cleanup, no functional change intended. Suggested-by: Ingo Molnar <mingo@eltu.hu> Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Jim Keniston <jkenisto@linux.vnet.ibm.com> Cc: Linux-mm <linux-mm@kvack.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Christoph Hellwig <hch@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20120312092555.5379.942.sendpatchset@srdronam.in.ibm.com [ Fixed the math-emu build ] Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | Merge branch 'x86-x32-for-linus' of ↵Linus Torvalds2012-03-291-16/+122
|\ \ | |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x32 support for x86-64 from Ingo Molnar: "This tree introduces the X32 binary format and execution mode for x86: 32-bit data space binaries using 64-bit instructions and 64-bit kernel syscalls. This allows applications whose working set fits into a 32 bits address space to make use of 64-bit instructions while using a 32-bit address space with shorter pointers, more compressed data structures, etc." Fix up trivial context conflicts in arch/x86/{Kconfig,vdso/vma.c} * 'x86-x32-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (71 commits) x32: Fix alignment fail in struct compat_siginfo x32: Fix stupid ia32/x32 inversion in the siginfo format x32: Add ptrace for x32 x32: Switch to a 64-bit clock_t x32: Provide separate is_ia32_task() and is_x32_task() predicates x86, mtrr: Use explicit sizing and padding for the 64-bit ioctls x86/x32: Fix the binutils auto-detect x32: Warn and disable rather than error if binutils too old x32: Only clear TIF_X32 flag once x32: Make sure TS_COMPAT is cleared for x32 tasks fs: Remove missed ->fds_bits from cessation use of fd_set structs internally fs: Fix close_on_exec pointer in alloc_fdtable x32: Drop non-__vdso weak symbols from the x32 VDSO x32: Fix coding style violations in the x32 VDSO code x32: Add x32 VDSO support x32: Allow x32 to be configured x32: If configured, add x32 system calls to system call tables x32: Handle process creation x32: Signal-related system calls x86: Add #ifdef CONFIG_COMPAT to <asm/sys_ia32.h> ...
| * x32: Signal-related system callsH. Peter Anvin2012-02-201-1/+117
| | | | | | | | | | | | | | | | | | | | | | x32 uses the 64-bit signal frame format, obviously, but there are some structures which mixes that with pointers or sizeof(long) types, as such we have to create a handful of system calls specific to x32. By and large these are a mixture of the 64-bit and the compat system calls. Originally-by: H. J. Lu <hjl.tools@gmail.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
| * x32: Export setup/restore_sigcontext from signal.cH. Peter Anvin2012-02-201-6/+4
| | | | | | | | | | | | | | Export setup_sigcontext() and restore_sigcontext() from signal.c, so we can use the 64-bit versions verbatim for x32. Signed-off-by: H. Peter Anvin <hpa@zytor.com>
| * x86: Move some signal-handling definitions to a common headerH. Peter Anvin2012-02-201-9/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There are some definitions which are duplicated between kernel/signal.c and ia32/ia32_signal.c; move them to a common header file. Rather than adding stuff to existing header files which contain data structures, create a new header file; hence the slightly odd name ("all the good ones were taken.") Note: nothing relied on signal_fault() being defined in <asm/ptrace.h>. Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* | i387: Split up <asm/i387.h> into exported and internal interfacesLinus Torvalds2012-02-211-0/+1
|/ | | | | | | | | | | | | | | | | | | | | | | | | While various modules include <asm/i387.h> to get access to things we actually *intend* for them to use, most of that header file was really pretty low-level internal stuff that we really don't want to expose to others. So split the header file into two: the small exported interfaces remain in <asm/i387.h>, while the internal definitions that are only used by core architecture code are now in <asm/fpu-internal.h>. The guiding principle for this was to expose functions that we export to modules, and leave them in <asm/i387.h>, while stuff that is used by task switching or was marked GPL-only is in <asm/fpu-internal.h>. The fpu-internal.h file could be further split up too, especially since arch/x86/kvm/ uses some of the remaining stuff for its module. But that kvm usage should probably be abstracted out a bit, and at least now the internal FPU accessor functions are much more contained. Even if it isn't perhaps as contained as it _could_ be. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1202211340330.5354@i5.linux-foundation.org Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* signal: add block_sigmask() for adding sigmask to current->blockedMatt Fleming2012-01-101-5/+1
| | | | | | | | | | | | | | | | | Abstract the code sequence for adding a signal handler's sa_mask to current->blocked because the sequence is identical for all architectures. Furthermore, in the past some architectures actually got this code wrong, so introduce a wrapper that all architectures can use. Signed-off-by: Matt Fleming <matt.fleming@intel.com> Signed-off-by: Oleg Nesterov <oleg@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Tejun Heo <tj@kernel.org> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* x86: Kill handle_signal()->set_fs()Oleg Nesterov2011-07-141-9/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | handle_signal()->set_fs() has a nice comment which explains what set_fs() is, but it doesn't explain why it is needed and why it depends on CONFIG_X86_64. Afaics, the history of this confusion is: 1. I guess today nobody can explain why it was needed in arch/i386/kernel/signal.c, perhaps it was always wrong. This predates 2.4.0 kernel. 2. then it was copy-and-past'ed to the new x86_64 arch. 3. then it was removed from i386 (but not from x86_64) by b93b6ca3 "i386: remove unnecessary code". 4. then it was reintroduced under CONFIG_X86_64 when x86 unified i386 and x86_64, because the patch above didn't touch x86_64. Remove it. ->addr_limit should be correct. Even if it was possible that it is wrong, it is too late to fix it after setup_rt_frame(). Linus commented in: http://lkml.kernel.org/r/alpine.LFD.0.999.0707170902570.19166@woody.linux-foundation.org ... about the equivalent bit from i386: Heh. I think it's entirely historical. Please realize that the whole reason that function is called "set_fs()" is that it literally used to set the %fs segment register, not "->addr_limit". So I think the "set_fs(USER_DS)" is there _only_ to match the other regs->xds = __USER_DS; regs->xes = __USER_DS; regs->xss = __USER_DS; regs->xcs = __USER_CS; things, and never mattered. And now it matters even less, and has been copied to all other architectures where it is just totally insane. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Link: http://lkml.kernel.org/r/20110710164424.GA20261@redhat.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
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