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2012-07-22Merge branch 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-10/+7
Pull debug-for-linus git tree from Ingo Molnar. Fix up trivial conflict in arch/x86/kernel/cpu/perf_event_intel.c due to a printk() having changed to a pr_info() differently in the two branches. * 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86: Move call to print_modules() out of show_regs() x86/mm: Mark free_initrd_mem() as __init x86/microcode: Mark microcode_id[] as __initconst x86/nmi: Clean up register_nmi_handler() usage x86: Save cr2 in NMI in case NMIs take a page fault (for i386) x86: Remove cmpxchg from i386 NMI nesting code x86: Save cr2 in NMI in case NMIs take a page fault x86/debug: Add KERN_<LEVEL> to bare printks, convert printks to pr_<level>
2012-07-14vsyscall_64: add missing ifdef CONFIG_SECCOMPWill Drewry1-0/+4
vsyscall_seccomp introduced a dependency on __secure_computing. On configurations with CONFIG_SECCOMP disabled, compilation will fail. Reported-by: feng xiangjun <fengxj325@gmail.com> Signed-off-by: Will Drewry <wad@chromium.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-13x86/vsyscall: allow seccomp filter in vsyscall=emulateWill Drewry1-4/+31
If a seccomp filter program is installed, older static binaries and distributions with older libc implementations (glibc 2.13 and earlier) that rely on vsyscall use will be terminated regardless of the filter program policy when executing time, gettimeofday, or getcpu. This is only the case when vsyscall emulation is in use (vsyscall=emulate is the default). This patch emulates system call entry inside a vsyscall=emulate by populating regs->ax and regs->orig_ax with the system call number prior to calling into seccomp such that all seccomp-dependencies function normally. Additionally, system call return behavior is emulated in line with other vsyscall entrypoints for the trace/trap cases. [ v2: fixed ip and sp on SECCOMP_RET_TRAP/TRACE (thanks to luto@mit.edu) ] Reported-and-tested-by: Owen Kibel <qmewlo@gmail.com> Signed-off-by: Will Drewry <wad@chromium.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-06-06x86/debug: Add KERN_<LEVEL> to bare printks, convert printks to pr_<level>Joe Perches1-10/+7
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>
2012-04-06x86: vsyscall: Use NULL instead 0 for a pointer argumentEmil Goode1-3/+3
This patch silences the following sparse warning: arch/x86/kernel/vsyscall_64.c:250:34: warning: Using plain integer as NULL pointer Signed-off-by: Emil Goode <emilgoode@gmail.com> Acked-by: Andy Lutomirski <luto@amacapital.net> Cc: john.stultz@linaro.org Link: http://lkml.kernel.org/r/1333306084-3776-1-git-send-email-emilgoode@gmail.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-03-29Merge branch 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-1/+1
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
2012-03-24x86: vdso: Put declaration before codeThomas Gleixner1-1/+2
Sigh, warnings are there for a reason. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: John Stultz <john.stultz@linaro.org>
2012-03-23x86-64: Simplify and optimize vdso clock_gettime monotonic variantsAndy Lutomirski1-1/+9
We used to store the wall-to-monotonic offset and the realtime base. It's faster to precompute the monotonic base. This is about a 3% speedup on Sandy Bridge for CLOCK_MONOTONIC. It's much more impressive for CLOCK_MONOTONIC_COARSE. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: John Stultz <john.stultz@linaro.org>
2012-03-15x86: vdso: Use seqcount instead of seqlockThomas Gleixner1-8/+3
The update of the vdso data happens under xtime_lock, so adding a nested lock is pointless. Just use a seqcount to sync the readers. Reviewed-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
2012-03-15x86: vdso: Remove bogus locking in update_vsyscall_tz()Thomas Gleixner1-5/+0
Changing the sequence count in update_vsyscall_tz() is completely pointless. The vdso code copies the data unprotected. There is no point to change this as sys_tz is nowhere protected at all. See sys_gettimeofday(). Reviewed-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
2012-03-13x86: Rename trap_no to trap_nr in thread_structSrikar Dronamraju1-1/+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>
2011-12-05x86: Default to vsyscall=emulateAndy Lutomirski1-1/+1
This essentially reverts: 2b666859ec32: x86: Default to vsyscall=native for now The ABI breakage should now be fixed by: commit 48c4206f5b02f28c4c78a1f5b491d3772fb64fb9 Author: Andy Lutomirski <luto@mit.edu> Date: Thu Oct 20 08:48:19 2011 -0700 x86-64: Set siginfo and context on vsyscall emulation faults Signed-off-by: Andy Lutomirski <luto@amacapital.net> Cc: richard -rw- weinberger <richard.weinberger@gmail.com> Cc: Adrian Bunk <bunk@stusta.de> Cc: H. Peter Anvin <hpa@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/93154af3b2b6d208906ae02d80d92cf60c6fa94f.1320712291.git.luto@amacapital.net Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-12-05x86-64: Set siginfo and context on vsyscall emulation faultsAndy Lutomirski1-8/+67
To make this work, we teach the page fault handler how to send signals on failed uaccess. This only works for user addresses (kernel addresses will never hit the page fault handler in the first place), so we need to generate signals for those separately. This gets the tricky case right: if the user buffer spans multiple pages and only the second page is invalid, we set cr2 and si_addr correctly. UML relies on this behavior to "fault in" pages as needed. We steal a bit from thread_info.uaccess_err to enable this. Before this change, uaccess_err was a 32-bit boolean value. This fixes issues with UML when vsyscall=emulate. Reported-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andy Lutomirski <luto@amacapital.net> Cc: richard -rw- weinberger <richard.weinberger@gmail.com> Cc: H. Peter Anvin <hpa@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/4c8f91de7ec5cd2ef0f59521a04e1015f11e42b4.1320712291.git.luto@amacapital.net Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-31x86: fix implicit include of <linux/topology.h> in vsyscall_64Paul Gortmaker1-0/+1
In removing the presence of <linux/module.h> from some of the more common <linux/something.h> files, this implict include of <linux/topology.h> was uncovered. CC arch/x86/kernel/vsyscall_64.o arch/x86/kernel/vsyscall_64.c: In function ‘vsyscall_set_cpu’: arch/x86/kernel/vsyscall_64.c:259: error: implicit declaration of function ‘cpu_to_node’ Explicitly call it out so the cleanup can take place. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-11x86: Default to vsyscall=native for nowAdrian Bunk1-1/+1
This UML breakage: linux-2.6.30.1[3800] vsyscall fault (exploit attempt?) ip:ffffffffff600000 cs:33 sp:7fbfb9c498 ax:ffffffffff600000 si:0 di:606790 linux-2.6.30.1[3856] vsyscall fault (exploit attempt?) ip:ffffffffff600000 cs:33 sp:7fbfb13168 ax:ffffffffff600000 si:0 di:606790 Is caused by commit 3ae36655 ("x86-64: Rework vsyscall emulation and add vsyscall= parameter") - the vsyscall emulation code is not fully cooked yet as UML relies on some rather fragile SIGSEGV semantics. Linus suggested in https://lkml.org/lkml/2011/8/9/376 to default to vsyscall=native for now, this patch implements that. Signed-off-by: Adrian Bunk <bunk@kernel.org> Acked-by: Andrew Lutomirski <luto@mit.edu> Cc: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/r/20111005214047.GE14406@localhost.pp.htv.fi Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-08-10x86-64: Rework vsyscall emulation and add vsyscall= parameterAndy Lutomirski1-30/+49
There are three choices: vsyscall=native: Vsyscalls are native code that issues the corresponding syscalls. vsyscall=emulate (default): Vsyscalls are emulated by instruction fault traps, tested in the bad_area path. The actual contents of the vsyscall page is the same as the vsyscall=native case except that it's marked NX. This way programs that make assumptions about what the code in the page does will not be confused when they read that code. vsyscall=none: Trying to execute a vsyscall will segfault. Signed-off-by: Andy Lutomirski <luto@mit.edu> Link: http://lkml.kernel.org/r/8449fb3abf89851fd6b2260972666a6f82542284.1312988155.git.luto@mit.edu Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-08-10x86: Remove unnecessary compile flag tweaks for vsyscall codeAndy Lutomirski1-3/+0
As of commit 98d0ac38ca7b1b7a552c9a2359174ff84decb600 Author: Andy Lutomirski <luto@mit.edu> Date: Thu Jul 14 06:47:22 2011 -0400 x86-64: Move vread_tsc and vread_hpet into the vDSO user code no longer directly calls into code in arch/x86/kernel/, so we don't need compile flag hacks to make it safe. All vdso code is in the vdso directory now. Signed-off-by: Andy Lutomirski <luto@mit.edu> Link: http://lkml.kernel.org/r/835cd05a4c7740544d09723d6ba48f4406f9826c.1312988155.git.luto@mit.edu Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-08-04x86-64: Add vsyscall:emulate_vsyscall trace eventAndy Lutomirski1-0/+6
Vsyscall emulation is slow, so make it easy to track down. Signed-off-by: Andy Lutomirski <luto@mit.edu> Link: http://lkml.kernel.org/r/cdaad7da946a80b200df16647c1700db3e1171e9.1312378163.git.luto@mit.edu Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-08-04x86-64: Add user_64bit_mode paravirt opAndy Lutomirski1-5/+1
Three places in the kernel assume that the only long mode CPL 3 selector is __USER_CS. This is not true on Xen -- Xen's sysretq changes cs to the magic value 0xe033. Two of the places are corner cases, but as of "x86-64: Improve vsyscall emulation CS and RIP handling" (c9712944b2a12373cb6ff8059afcfb7e826a6c54), vsyscalls will segfault if called with Xen's extra CS selector. This causes a panic when older init builds die. It seems impossible to make Xen use __USER_CS reliably without taking a performance hit on every system call, so this fixes the tests instead with a new paravirt op. It's a little ugly because ptrace.h can't include paravirt.h. Signed-off-by: Andy Lutomirski <luto@mit.edu> Link: http://lkml.kernel.org/r/f4fcb3947340d9e96ce1054a432f183f9da9db83.1312378163.git.luto@mit.edu Reported-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-07-14x86-64: Move vread_tsc and vread_hpet into the vDSOAndy Lutomirski1-1/+1
The vsyscall page now consists entirely of trap instructions. Cc: John Stultz <johnstul@us.ibm.com> Signed-off-by: Andy Lutomirski <luto@mit.edu> Link: http://lkml.kernel.org/r/637648f303f2ef93af93bae25186e9a1bea093f5.1310639973.git.luto@mit.edu Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-07-13clocksource: Replace vread with generic arch dataAndy Lutomirski1-1/+1
The vread field was bloating struct clocksource everywhere except x86_64, and I want to change the way this works on x86_64, so let's split it out into per-arch data. Cc: x86@kernel.org Cc: Clemens Ladisch <clemens@ladisch.de> Cc: linux-ia64@vger.kernel.org Cc: Tony Luck <tony.luck@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: John Stultz <johnstul@us.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andy Lutomirski <luto@mit.edu> Link: http://lkml.kernel.org/r/3ae5ec76a168eaaae63f08a2a1060b91aa0b7759.1310563276.git.luto@mit.edu Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-07-13x86-64: Improve vsyscall emulation CS and RIP handlingAndy Lutomirski1-20/+41
Three fixes here: - Send SIGSEGV if called from compat code or with a funny CS. - Don't BUG on impossible addresses. - Add a missing local_irq_disable. This patch also removes an unused variable. Signed-off-by: Andy Lutomirski <luto@mit.edu> Link: http://lkml.kernel.org/r/6fb2b13ab39b743d1e4f466eef13425854912f7f.1310563276.git.luto@mit.edu Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-06-07x86-64: Emulate legacy vsyscallsAndy Lutomirski1-139/+122
There's a fair amount of code in the vsyscall page. It contains a syscall instruction (in the gettimeofday fallback) and who knows what will happen if an exploit jumps into the middle of some other code. Reduce the risk by replacing the vsyscalls with short magic incantations that cause the kernel to emulate the real vsyscalls. These incantations are useless if entered in the middle. This causes vsyscalls to be a little more expensive than real syscalls. Fortunately sensible programs don't use them. The only exception is time() which is still called by glibc through the vsyscall - but calling time() millions of times per second is not sensible. glibc has this fixed in the development tree. This patch is not perfect: the vread_tsc and vread_hpet functions are still at a fixed address. Fixing that might involve making alternative patching work in the vDSO. Signed-off-by: Andy Lutomirski <luto@mit.edu> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Jesper Juhl <jj@chaosbits.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Jan Beulich <JBeulich@novell.com> Cc: richard -rw- weinberger <richard.weinberger@gmail.com> Cc: Mikael Pettersson <mikpe@it.uu.se> Cc: Andi Kleen <andi@firstfloor.org> Cc: Brian Gerst <brgerst@gmail.com> Cc: Louis Rilling <Louis.Rilling@kerlabs.com> Cc: Valdis.Kletnieks@vt.edu Cc: pageexec@freemail.hu Link: http://lkml.kernel.org/r/e64e1b3c64858820d12c48fa739efbd1485e79d5.1307292171.git.luto@mit.edu [ Removed the CONFIG option - it's simpler to just do it unconditionally. Tidied up the code as well. ] Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-06-06x86-64: Remove vsyscall number 3 (venosys)Andy Lutomirski1-5/+0
It just segfaults since April 2008 (a4928cff), so I'm pretty sure that nothing uses it. And having an empty section makes the linker script a bit fragile. Signed-off-by: Andy Lutomirski <luto@mit.edu> Cc: Jesper Juhl <jj@chaosbits.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Jan Beulich <JBeulich@novell.com> Cc: richard -rw- weinberger <richard.weinberger@gmail.com> Cc: Mikael Pettersson <mikpe@it.uu.se> Cc: Andi Kleen <andi@firstfloor.org> Cc: Brian Gerst <brgerst@gmail.com> Cc: Louis Rilling <Louis.Rilling@kerlabs.com> Cc: Valdis.Kletnieks@vt.edu Cc: pageexec@freemail.hu Link: http://lkml.kernel.org/r/4a4abcf47ecadc269f2391a313576fe6d06acef7.1307292171.git.luto@mit.edu Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-06-05x86-64: Remove kernel.vsyscall64 sysctlAndy Lutomirski1-33/+1
It's unnecessary overhead in code that's supposed to be highly optimized. Removing it allows us to remove one of the two syscall instructions in the vsyscall page. The only sensible use for it is for UML users, and it doesn't fully address inconsistent vsyscall results on UML. The real fix for UML is to stop using vsyscalls entirely. Signed-off-by: Andy Lutomirski <luto@mit.edu> Cc: Jesper Juhl <jj@chaosbits.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Jan Beulich <JBeulich@novell.com> Cc: richard -rw- weinberger <richard.weinberger@gmail.com> Cc: Mikael Pettersson <mikpe@it.uu.se> Cc: Andi Kleen <andi@firstfloor.org> Cc: Brian Gerst <brgerst@gmail.com> Cc: Louis Rilling <Louis.Rilling@kerlabs.com> Cc: Valdis.Kletnieks@vt.edu Cc: pageexec@freemail.hu Link: http://lkml.kernel.org/r/973ae803fe76f712da4b2740e66dccf452d3b1e4.1307292171.git.luto@mit.edu Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-06-05x86-64: Give vvars their own pageAndy Lutomirski1-0/+5
Move vvars out of the vsyscall page into their own page and mark it NX. Without this patch, an attacker who can force a daemon to call some fixed address could wait until the time contains, say, 0xCD80, and then execute the current time. Signed-off-by: Andy Lutomirski <luto@mit.edu> Cc: Jesper Juhl <jj@chaosbits.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Jan Beulich <JBeulich@novell.com> Cc: richard -rw- weinberger <richard.weinberger@gmail.com> Cc: Mikael Pettersson <mikpe@it.uu.se> Cc: Andi Kleen <andi@firstfloor.org> Cc: Brian Gerst <brgerst@gmail.com> Cc: Louis Rilling <Louis.Rilling@kerlabs.com> Cc: Valdis.Kletnieks@vt.edu Cc: pageexec@freemail.hu Link: http://lkml.kernel.org/r/b1460f81dc4463d66ea3f2b5ce240f58d48effec.1307292171.git.luto@mit.edu Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-05-26Merge branch 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tipLinus Torvalds1-26/+20
* 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86: vdso: Remove unused variable x86-64: Optimize vDSO time() x86-64: Add time to vDSO x86-64: Turn off -pg and turn on -foptimize-sibling-calls for vDSO x86-64: Move vread_tsc into a new file with sensible options x86-64: Vclock_gettime(CLOCK_MONOTONIC) can't ever see nsec < 0 x86-64: Don't generate cmov in vread_tsc x86-64: Remove unnecessary barrier in vread_tsc x86-64: Clean up vdso/kernel shared variables
2011-05-24seqlock: Get rid of SEQLOCK_UNLOCKEDEric Dumazet1-1/+1
All static seqlock should be initialized with the lockdep friendly __SEQLOCK_UNLOCKED() macro. Remove legacy SEQLOCK_UNLOCKED() macro. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Cc: David Miller <davem@davemloft.net> Link: http://lkml.kernel.org/r/%3C1306238888.3026.31.camel%40edumazet-laptop%3E Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-05-24x86-64: Clean up vdso/kernel shared variablesAndy Lutomirski1-26/+20
Variables that are shared between the vdso and the kernel are currently a bit of a mess. They are each defined with their own magic, they are accessed differently in the kernel, the vsyscall page, and the vdso, and one of them (vsyscall_clock) doesn't even really exist. This changes them all to use a common mechanism. All of them are delcared in vvar.h with a fixed address (validated by the linker script). In the kernel (as before), they look like ordinary read-write variables. In the vsyscall page and the vdso, they are accessed through a new macro VVAR, which gives read-only access. The vdso is now loaded verbatim into memory without any fixups. As a side bonus, access from the vdso is faster because a level of indirection is removed. While we're at it, pack jiffies and vgetcpu_mode into the same cacheline. Signed-off-by: Andy Lutomirski <luto@mit.edu> Cc: Andi Kleen <andi@firstfloor.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Borislav Petkov <bp@amd64.org> Link: http://lkml.kernel.org/r/%3C7357882fbb51fa30491636a7b6528747301b7ee9.1306156808.git.luto%40mit.edu%3E Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2010-07-27timkeeping: Fix update_vsyscall to provide wall_to_monotonic offsetJohn Stultz1-3/+3
update_vsyscall() did not provide the wall_to_monotoinc offset, so arch specific implementations tend to reference wall_to_monotonic directly. This limits future cleanups in the timekeeping core, so this patch fixes the update_vsyscall interface to provide wall_to_monotonic, allowing wall_to_monotonic to be made static as planned in Documentation/feature-removal-schedule.txt Signed-off-by: John Stultz <johnstul@us.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Anton Blanchard <anton@samba.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Tony Luck <tony.luck@intel.com> LKML-Reference: <1279068988-21864-7-git-send-email-johnstul@us.ibm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2010-07-27x86: Fix vtime/file timestamp inconsistenciesJohn Stultz1-3/+8
Due to vtime calling vgettimeofday(), its possible that an application could call time();create("stuff",O_RDRW); only to see the file's creation timestamp to be before the value returned by time. A similar way to reproduce the issue is to compare the vsyscall time() with the syscall time(), and observe ordering issues. The modified test case from Oleg Nesterov below can illustrate this: int main(void) { time_t sec1,sec2; do { sec1 = time(&sec2); sec2 = syscall(__NR_time, NULL); } while (sec1 <= sec2); printf("vtime: %d.000000\n", sec1); printf("time: %d.000000\n", sec2); return 0; } The proper fix is to make vtime use the same time value as current_kernel_time() (which is exported via update_vsyscall) instead of vgettime(). Thanks to Jiri Olsa for bringing up the issue and catching bugs in earlier verisons of this fix. Signed-off-by: John Stultz <johnstul@us.ibm.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Oleg Nesterov <oleg@redhat.com> LKML-Reference: <1279068988-21864-2-git-send-email-johnstul@us.ibm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2010-03-01x86: Raise vsyscall priority on hotplug notifier chainSheng Yang1-1/+2
KVM need vsyscall_init() to initialize MSR_TSC_AUX before it read the value. Per Avi's suggestion, this patch raised vsyscall priority on hotplug notifier chain, to 30. CC: Ingo Molnar <mingo@elte.hu> CC: linux-kernel@vger.kernel.org Signed-off-by: Sheng Yang <sheng@linux.intel.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-12-08Merge branch 'timers-for-linus-urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tipLinus Torvalds1-2/+3
* 'timers-for-linus-urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: hrtimer: Fix /proc/timer_list regression itimers: Fix racy writes to cpu_itimer fields timekeeping: Fix clock_gettime vsyscall time warp
2009-11-17timekeeping: Fix clock_gettime vsyscall time warpLin Ming1-2/+3
Since commit 0a544198 "timekeeping: Move NTP adjusted clock multiplier to struct timekeeper" the clock multiplier of vsyscall is updated with the unmodified clock multiplier of the clock source and not with the NTP adjusted multiplier of the timekeeper. This causes user space observerable time warps: new CLOCK-warp maximum: 120 nsecs, 00000025c337c537 -> 00000025c337c4bf Add a new argument "mult" to update_vsyscall() and hand in the timekeeping internal NTP adjusted multiplier. Signed-off-by: Lin Ming <ming.m.lin@intel.com> Cc: "Zhang Yanmin" <yanmin_zhang@linux.intel.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Tony Luck <tony.luck@intel.com> LKML-Reference: <1258436990.17765.83.camel@minggr.sh.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-11-12sysctl x86: Remove dead binary sysctl supportEric W. Biederman1-1/+1
Now that sys_sysctl is a generic wrapper around /proc/sys .ctl_name and .strategy members of sysctl tables are dead code. Remove them. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2009-09-24sysctl: remove "struct file *" argument of ->proc_handlerAlexey Dobriyan1-9/+1
It's unused. It isn't needed -- read or write flag is already passed and sysctl shouldn't care about the rest. It _was_ used in two places at arch/frv for some reason. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: David Howells <dhowells@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: "David S. Miller" <davem@davemloft.net> Cc: James Morris <jmorris@namei.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-08-21time: Introduce CLOCK_REALTIME_COARSEjohn stultz1-0/+1
After talking with some application writers who want very fast, but not fine-grained timestamps, I decided to try to implement new clock_ids to clock_gettime(): CLOCK_REALTIME_COARSE and CLOCK_MONOTONIC_COARSE which returns the time at the last tick. This is very fast as we don't have to access any hardware (which can be very painful if you're using something like the acpi_pm clocksource), and we can even use the vdso clock_gettime() method to avoid the syscall. The only trade off is you only get low-res tick grained time resolution. This isn't a new idea, I know Ingo has a patch in the -rt tree that made the vsyscall gettimeofday() return coarse grained time when the vsyscall64 sysctrl was set to 2. However this affects all applications on a system. With this method, applications can choose the proper speed/granularity trade-off for themselves. Signed-off-by: John Stultz <johnstul@us.ibm.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: nikolag@ca.ibm.com Cc: Darren Hart <dvhltc@us.ibm.com> Cc: arjan@infradead.org Cc: jonathan@jonmasters.org LKML-Reference: <1250734414.6897.5.camel@localhost.localdomain> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-05-28x86: move rdtsc_barrier() into the TSC vread methodPetr Tesarik1-8/+0
The *fence instructions were moved to vsyscall_64.c by commit cb9e35dce94a1b9c59d46224e8a94377d673e204. But this breaks the vDSO, because vread methods are also called from there. Besides, the synchronization might be unnecessary for other time sources than TSC. [ Impact: fix potential time warp in VDSO ] Signed-off-by: Petr Tesarik <ptesarik@suse.cz> LKML-Reference: <9d0ea9ea0f866bdc1f4d76831221ae117f11ea67.1243241859.git.ptesarik@suse.cz> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: <stable@kernel.org>
2008-12-28Merge branch 'tracing-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tipLinus Torvalds1-0/+3
* 'tracing-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (241 commits) sched, trace: update trace_sched_wakeup() tracing/ftrace: don't trace on early stage of a secondary cpu boot, v3 Revert "x86: disable X86_PTRACE_BTS" ring-buffer: prevent false positive warning ring-buffer: fix dangling commit race ftrace: enable format arguments checking x86, bts: memory accounting x86, bts: add fork and exit handling ftrace: introduce tracing_reset_online_cpus() helper tracing: fix warnings in kernel/trace/trace_sched_switch.c tracing: fix warning in kernel/trace/trace.c tracing/ring-buffer: remove unused ring_buffer size trace: fix task state printout ftrace: add not to regex on filtering functions trace: better use of stack_trace_enabled for boot up code trace: add a way to enable or disable the stack tracer x86: entry_64 - introduce FTRACE_ frame macro v2 tracing/ftrace: add the printk-msg-only option tracing/ftrace: use preempt_enable_no_resched_notrace in ring_buffer_time_stamp() x86, bts: correctly report invalid bts records ... Fixed up trivial conflict in scripts/recordmcount.pl due to SH bits being already partly merged by the SH merge.
2008-11-12trace: rename unlikely profiler to branch profilerSteven Rostedt1-1/+1
Impact: name change of unlikely tracer and profiler Ingo Molnar suggested changing the config from UNLIKELY_PROFILE to BRANCH_PROFILING. I never did like the "unlikely" name so I went one step farther, and renamed all the unlikely configurations to a "BRANCH" variant. Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-12tracing: branch tracer, fix vdso crashIngo Molnar1-7/+2
Impact: fix bootup crash the branch tracer missed arch/x86/vdso/vclock_gettime.c from disabling tracing, which caused such bootup crashes: [ 201.840097] init[1]: segfault at 7fffed3fe7c0 ip 00007fffed3fea2e sp 000077 also clean up the ugly ifdefs in arch/x86/kernel/vsyscall_64.c by creating DISABLE_UNLIKELY_PROFILE facility for code to turn off instrumentation on a per file basis. Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-12tracing: profile likely and unlikely annotationsSteven Rostedt1-0/+8
Impact: new unlikely/likely profiler Andrew Morton recently suggested having an in-kernel way to profile likely and unlikely macros. This patch achieves that goal. When configured, every(*) likely and unlikely macro gets a counter attached to it. When the condition is hit, the hit and misses of that condition are recorded. These numbers can later be retrieved by: /debugfs/tracing/profile_likely - All likely markers /debugfs/tracing/profile_unlikely - All unlikely markers. # cat /debug/tracing/profile_unlikely | head correct incorrect % Function File Line ------- --------- - -------- ---- ---- 2167 0 0 do_arch_prctl process_64.c 832 0 0 0 do_arch_prctl process_64.c 804 2670 0 0 IS_ERR err.h 34 71230 5693 7 __switch_to process_64.c 673 76919 0 0 __switch_to process_64.c 639 43184 33743 43 __switch_to process_64.c 624 12740 64181 83 __switch_to process_64.c 594 12740 64174 83 __switch_to process_64.c 590 # cat /debug/tracing/profile_unlikely | \ awk '{ if ($3 > 25) print $0; }' |head -20 44963 35259 43 __switch_to process_64.c 624 12762 67454 84 __switch_to process_64.c 594 12762 67447 84 __switch_to process_64.c 590 1478 595 28 syscall_get_error syscall.h 51 0 2821 100 syscall_trace_leave ptrace.c 1567 0 1 100 native_smp_prepare_cpus smpboot.c 1237 86338 265881 75 calc_delta_fair sched_fair.c 408 210410 108540 34 calc_delta_mine sched.c 1267 0 54550 100 sched_info_queued sched_stats.h 222 51899 66435 56 pick_next_task_fair sched_fair.c 1422 6 10 62 yield_task_fair sched_fair.c 982 7325 2692 26 rt_policy sched.c 144 0 1270 100 pre_schedule_rt sched_rt.c 1261 1268 48073 97 pick_next_task_rt sched_rt.c 884 0 45181 100 sched_info_dequeued sched_stats.h 177 0 15 100 sched_move_task sched.c 8700 0 15 100 sched_move_task sched.c 8690 53167 33217 38 schedule sched.c 4457 0 80208 100 sched_info_switch sched_stats.h 270 30585 49631 61 context_switch sched.c 2619 # cat /debug/tracing/profile_likely | awk '{ if ($3 > 25) print $0; }' 39900 36577 47 pick_next_task sched.c 4397 20824 15233 42 switch_mm mmu_context_64.h 18 0 7 100 __cancel_work_timer workqueue.c 560 617 66484 99 clocksource_adjust timekeeping.c 456 0 346340 100 audit_syscall_exit auditsc.c 1570 38 347350 99 audit_get_context auditsc.c 732 0 345244 100 audit_syscall_entry auditsc.c 1541 38 1017 96 audit_free auditsc.c 1446 0 1090 100 audit_alloc auditsc.c 862 2618 1090 29 audit_alloc auditsc.c 858 0 6 100 move_masked_irq migration.c 9 1 198 99 probe_sched_wakeup trace_sched_switch.c 58 2 2 50 probe_wakeup trace_sched_wakeup.c 227 0 2 100 probe_wakeup_sched_switch trace_sched_wakeup.c 144 4514 2090 31 __grab_cache_page filemap.c 2149 12882 228786 94 mapping_unevictable pagemap.h 50 4 11 73 __flush_cpu_slab slub.c 1466 627757 330451 34 slab_free slub.c 1731 2959 61245 95 dentry_lru_del_init dcache.c 153 946 1217 56 load_elf_binary binfmt_elf.c 904 102 82 44 disk_put_part genhd.h 206 1 1 50 dst_gc_task dst.c 82 0 19 100 tcp_mss_split_point tcp_output.c 1126 As you can see by the above, there's a bit of work to do in rethinking the use of some unlikelys and likelys. Note: the unlikely case had 71 hits that were more than 25%. Note: After submitting my first version of this patch, Andrew Morton showed me a version written by Daniel Walker, where I picked up the following ideas from: 1) Using __builtin_constant_p to avoid profiling fixed values. 2) Using __FILE__ instead of instruction pointers. 3) Using the preprocessor to stop all profiling of likely annotations from vsyscall_64.c. Thanks to Andrew Morton, Arjan van de Ven, Theodore Tso and Ingo Molnar for their feed back on this patch. (*) Not ever unlikely is recorded, those that are used by vsyscalls (a few of them) had to have profiling disabled. Signed-off-by: Steven Rostedt <srostedt@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Theodore Tso <tytso@mit.edu> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-08x86: clean up rdtsc_barrier() useIngo Molnar1-0/+9
Impact: cleanup Move rdtsc_barrier() use to vsyscall_64.c where it's relied on, and point out its role in the context of its use. Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-15Merge branch 'generic-ipi' into generic-ipi-for-linusIngo Molnar1-2/+2
Conflicts: arch/powerpc/Kconfig arch/s390/kernel/time.c arch/x86/kernel/apic_32.c arch/x86/kernel/cpu/perfctr-watchdog.c arch/x86/kernel/i8259_64.c arch/x86/kernel/ldt.c arch/x86/kernel/nmi_64.c arch/x86/kernel/smpboot.c arch/x86/xen/smp.c include/asm-x86/hw_irq_32.h include/asm-x86/hw_irq_64.h include/asm-x86/mach-default/irq_vectors.h include/asm-x86/mach-voyager/irq_vectors.h include/asm-x86/smp.h kernel/Makefile Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-14Merge branch 'auto-ftrace-next' into tracing/for-linusIngo Molnar1-1/+2
Conflicts: arch/x86/kernel/entry_32.S arch/x86/kernel/process_32.c arch/x86/kernel/process_64.c arch/x86/lib/Makefile include/asm-x86/irqflags.h kernel/Makefile kernel/sched.c Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-08x86, 64-bit: use write_gdt_entry in vsyscall_set_cpuJeremy Fitzhardinge1-6/+6
Use write_gdt_entry to generate the special vgetcpu descriptor in the vsyscall page. Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Cc: xen-devel <xen-devel@lists.xensource.com> Cc: Stephen Tweedie <sct@redhat.com> Cc: Eduardo Habkost <ehabkost@redhat.com> Cc: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-26on_each_cpu(): kill unused 'retry' parameterJens Axboe1-1/+1
It's not even passed on to smp_call_function() anymore, since that was removed. So kill it. Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-06-26smp_call_function: get rid of the unused nonatomic/retry argumentJens Axboe1-1/+1
It's never used and the comments refer to nonatomic and retry interchangably. So get rid of it. Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-05-23x86: add notrace annotations to vsyscall.Steven Rostedt1-1/+2
Add the notrace annotations to the vsyscall functions - there we are not in kernel context yet, so the tracer function cannot (and must not) be called. Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-04-24"make namespacecheck" fixesIngo Molnar1-1/+1
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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