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2009-09-17Merge branch 'x86-mce-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-mce-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (21 commits) x86, mce: Fix compilation with !CONFIG_DEBUG_FS in mce-severity.c x86, mce: CE in last bank prevents panic by unknown MCE x86, mce: Fake panic support for MCE testing x86, mce: Move debugfs mce dir creating to mce.c x86, mce: Support specifying raise mode for software MCE injection x86, mce: Support specifying context for software mce injection x86, mce: fix reporting of Thermal Monitoring mechanism enabled x86, mce: remove never executed code x86, mce: add missing __cpuinit tags x86, mce: fix "mce" boot option handling for CONFIG_X86_NEW_MCE x86, mce: don't log boot MCEs on Pentium M (model == 13) CPUs x86: mce: Lower maximum number of banks to architecture limit x86: mce: macros to compute banks MSRs x86: mce: Move per bank data in a single datastructure x86: mce: Move code in mce.c x86: mce: Rename CONFIG_X86_NEW_MCE to CONFIG_X86_MCE x86: mce: Remove old i386 machine check code x86: mce: Update X86_MCE description in x86/Kconfig x86: mce: Make CONFIG_X86_ANCIENT_MCE dependent on CONFIG_X86_MCE x86, mce: use atomic_inc_return() instead of add by 1 ... Manually fixed up trivial conflicts: Documentation/feature-removal-schedule.txt arch/x86/kernel/cpu/mcheck/mce.c
2009-09-02KEYS: Add a keyctl to install a process's session keyring on its parent [try #6]David Howells
Add a keyctl to install a process's session keyring onto its parent. This replaces the parent's session keyring. Because the COW credential code does not permit one process to change another process's credentials directly, the change is deferred until userspace next starts executing again. Normally this will be after a wait*() syscall. To support this, three new security hooks have been provided: cred_alloc_blank() to allocate unset security creds, cred_transfer() to fill in the blank security creds and key_session_to_parent() - which asks the LSM if the process may replace its parent's session keyring. The replacement may only happen if the process has the same ownership details as its parent, and the process has LINK permission on the session keyring, and the session keyring is owned by the process, and the LSM permits it. Note that this requires alteration to each architecture's notify_resume path. This has been done for all arches barring blackfin, m68k* and xtensa, all of which need assembly alteration to support TIF_NOTIFY_RESUME. This allows the replacement to be performed at the point the parent process resumes userspace execution. This allows the userspace AFS pioctl emulation to fully emulate newpag() and the VIOCSETTOK and VIOCSETTOK2 pioctls, all of which require the ability to alter the parent process's PAG membership. However, since kAFS doesn't use PAGs per se, but rather dumps the keys into the session keyring, the session keyring of the parent must be replaced if, for example, VIOCSETTOK is passed the newpag flag. This can be tested with the following program: #include <stdio.h> #include <stdlib.h> #include <keyutils.h> #define KEYCTL_SESSION_TO_PARENT 18 #define OSERROR(X, S) do { if ((long)(X) == -1) { perror(S); exit(1); } } while(0) int main(int argc, char **argv) { key_serial_t keyring, key; long ret; keyring = keyctl_join_session_keyring(argv[1]); OSERROR(keyring, "keyctl_join_session_keyring"); key = add_key("user", "a", "b", 1, keyring); OSERROR(key, "add_key"); ret = keyctl(KEYCTL_SESSION_TO_PARENT); OSERROR(ret, "KEYCTL_SESSION_TO_PARENT"); return 0; } Compiled and linked with -lkeyutils, you should see something like: [dhowells@andromeda ~]$ keyctl show Session Keyring -3 --alswrv 4043 4043 keyring: _ses 355907932 --alswrv 4043 -1 \_ keyring: _uid.4043 [dhowells@andromeda ~]$ /tmp/newpag [dhowells@andromeda ~]$ keyctl show Session Keyring -3 --alswrv 4043 4043 keyring: _ses 1055658746 --alswrv 4043 4043 \_ user: a [dhowells@andromeda ~]$ /tmp/newpag hello [dhowells@andromeda ~]$ keyctl show Session Keyring -3 --alswrv 4043 4043 keyring: hello 340417692 --alswrv 4043 4043 \_ user: a Where the test program creates a new session keyring, sticks a user key named 'a' into it and then installs it on its parent. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2009-07-09x86: mce: Rename CONFIG_X86_NEW_MCE to CONFIG_X86_MCEAndi Kleen
Drop the CONFIG_X86_NEW_MCE symbol and change all references to it to check for CONFIG_X86_MCE directly. No code changes Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-06-11Merge branch 'linus' into x86/mce3Ingo Molnar
Conflicts: arch/x86/kernel/cpu/mcheck/mce_64.c arch/x86/kernel/irq.c Merge reason: Resolve the conflicts above. Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-06-03x86, mce: support action-optional machine checksAndi Kleen
Newer Intel CPUs support a new class of machine checks called recoverable action optional. Action Optional means that the CPU detected some form of corruption in the background and tells the OS about using a machine check exception. The OS can then take appropiate action, like killing the process with the corrupted data or logging the event properly to disk. This is done by the new generic high level memory failure handler added in a earlier patch. The high level handler takes the address with the failed memory and does the appropiate action, like killing the process. In this version of the patch the high level handler is stubbed out with a weak function to not create a direct dependency on the hwpoison branch. The high level handler cannot be directly called from the machine check exception though, because it has to run in a defined process context to be able to sleep when taking VM locks (it is not expected to sleep for a long time, just do so in some exceptional cases like lock contention) Thus the MCE handler has to queue a work item for process context, trigger process context and then call the high level handler from there. This patch adds two path to process context: through a per thread kernel exit notify_user() callback or through a high priority work item. The first runs when the process exits back to user space, the other when it goes to sleep and there is no higher priority process. The machine check handler will schedule both, and whoever runs first will grab the event. This is done because quick reaction to this event is critical to avoid a potential more fatal machine check when the corruption is consumed. There is a simple lock less ring buffer to queue the corrupted addresses between the exception handler and the process context handler. Then in process context it just calls the high level VM code with the corrupted PFNs. The code adds the required code to extract the failed address from the CPU's machine check registers. It doesn't try to handle all possible cases -- the specification has 6 different ways to specify memory address -- but only the linear address. Most of the required checking has been already done earlier in the mce_severity rule checking engine. Following the Intel recommendations Action Optional errors are only enabled for known situations (encoded in MCACODs). The errors are ignored otherwise, because they are action optional. v2: Improve comment, disable preemption while processing ring buffer (reported by Ying Huang) Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-06-03x86, mce: rename mce_notify_user to mce_notify_irqAndi Kleen
Rename the mce_notify_user function to mce_notify_irq. The next patch will split the wakeup handling of interrupt context and of process context and it's better to give it a clearer name for this. Contains a fix from Ying Huang [ Impact: cleanup ] Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> Cc: Huang Ying <ying.huang@intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-05-28x86, mce: use 64bit machine check code on 32bitAndi Kleen
The 64bit machine check code is in many ways much better than the 32bit machine check code: it is more specification compliant, is cleaner, only has a single code base versus one per CPU, has better infrastructure for recovery, has a cleaner way to communicate with user space etc. etc. Use the 64bit code for 32bit too. This is the second attempt to do this. There was one a couple of years ago to unify this code for 32bit and 64bit. Back then this ran into some trouble with K7s and was reverted. I believe this time the K7 problems (and some others) are addressed. I went over the old handlers and was very careful to retain all quirks. But of course this needs a lot of testing on old systems. On newer 64bit capable systems I don't expect much problems because they have been already tested with the 64bit kernel. I made this a CONFIG for now that still allows to select the old machine check code. This is mostly to make testing easier, if someone runs into a problem we can ask them to try with the CONFIG switched. The new code is default y for more coverage. Once there is confidence the 64bit code works well on older hardware too the CONFIG_X86_OLD_MCE and the associated code can be easily removed. This causes a behaviour change for 32bit installations. They now have to install the mcelog package to be able to log corrected machine checks. The 64bit machine check code only handles CPUs which support the standard Intel machine check architecture described in the IA32 SDM. The 32bit code has special support for some older CPUs which have non standard machine check architectures, in particular WinChip C3 and Intel P5. I made those a separate CONFIG option and kept them for now. The WinChip variant could be probably removed without too much pain, it doesn't really do anything interesting. P5 is also disabled by default (like it was before) because many motherboards have it miswired, but according to Alan Cox a few embedded setups use that one. Forward ported/heavily changed version of old patch, original patch included review/fixes from Thomas Gleixner, Bert Wesarg. Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-04-06perf_counter: unify and fix delayed counter wakeupPeter Zijlstra
While going over the wakeup code I noticed delayed wakeups only work for hardware counters but basically all software counters rely on them. This patch unifies and generalizes the delayed wakeup to fix this issue. Since we're dealing with NMI context bits here, use a cmpxchg() based single link list implementation to track counters that have pending wakeups. [ This should really be generic code for delayed wakeups, but since we cannot use cmpxchg()/xchg() in generic code, I've let it live in the perf_counter code. -- Eric Dumazet could use it to aggregate the network wakeups. ] Furthermore, the x86 method of using TIF flags was flawed in that its quite possible to end up setting the bit on the idle task, loosing the wakeup. The powerpc method uses per-cpu storage and does appear to be sufficient. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Paul Mackerras <paulus@samba.org> Orig-LKML-Reference: <20090330171023.153932974@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-04-06Merge branch 'linus' into perfcounters/core-v2Ingo Molnar
Merge reason: we have gathered quite a few conflicts, need to merge upstream Conflicts: arch/powerpc/kernel/Makefile arch/x86/ia32/ia32entry.S arch/x86/include/asm/hardirq.h arch/x86/include/asm/unistd_32.h arch/x86/include/asm/unistd_64.h arch/x86/kernel/cpu/common.c arch/x86/kernel/irq.c arch/x86/kernel/syscall_table_32.S arch/x86/mm/iomap_32.c include/linux/sched.h kernel/Makefile Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-04-01x86: signal: check sas_ss_size instead of sas_ss_flags()Hiroshi Shimamoto
Impact: fix redundant and incorrect check Oleg Nesterov noticed wrt commit: 14fc9fb: x86: signal: check signal stack overflow properly >> No need to check SA_ONSTACK if we're already using alternate signal stack. > > Yes, but this also mean that we don't need sas_ss_flags() under > "if (!onsigstack)", Checking on_sig_stack() in sas_ss_flags() at get_sigframe() is redundant and not correct on 64 bit. To check sas_ss_size is enough. Reported-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com> Cc: roland@redhat.com LKML-Reference: <49CBB54C.5080201@ct.jp.nec.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-20x86: signal: check signal stack overflow properlyHiroshi Shimamoto
Impact: cleanup Check alternate signal stack overflow with proper stack pointer. The stack pointer of the next signal frame is different if that task has i387 state. On x86_64, redzone would be included. No need to check SA_ONSTACK if we're already using alternate signal stack. Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com> Cc: Roland McGrath <roland@redhat.com> LKML-Reference: <49C2874D.3080002@ct.jp.nec.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-03x86, signals: fix xine & firefox bustageHiroshi Shimamoto
Impact: fix bad frame in rt_sigreturn on 64-bit After commit 97286a2b64725aac2d584ddd1f94871f9991d5a1 some applications fail to return from signal handler: [ 145.150133] firefox[3250] bad frame in rt_sigreturn frame:00007f902b44eb28 ip:352e80b307 sp:7f902b44ef70 orax:ffffffffffffffff in libpthread-2.9.so[352e800000+17000] [ 665.519017] firefox[5420] bad frame in rt_sigreturn frame:00007faa8deaeb28 ip:352e80b307 sp:7faa8deaef70 orax:ffffffffffffffff in libpthread-2.9.so[352e800000+17000] The root cause is forgetting to keep 64 byte aligned value of fpstate for next stack pointer calculation. Reported-by: Jaswinder Singh Rajput <jaswinder@kernel.org> Reported-by: Mike Galbraith <efault@gmx.de> Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com> LKML-Reference: <49AC85C1.7060600@ct.jp.nec.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-28x86: signal: introduce helper align_sigframe()Hiroshi Shimamoto
Impact: cleanup Introduce helper align_sigframe() to align stack pointer for signal frame. Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-28x86: signal: unify get_sigframe()Hiroshi Shimamoto
Impact: cleanup Unify get_sigframe(). Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-28x86: signal: use 16 bytes boundary for rt_sigframeHiroshi Shimamoto
Impact: cleanup Supporting xsave/xrestore introduces 64 bytes boundary for save_i387_xstate(). 16 bytes boundary is OK for rt_sigframe. Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-28x86: signal: intrroduce get_sigframe() and replace get_sigstack()Hiroshi Shimamoto
Impact: cleanup Introduce get_sigframe() like 32-bit to replace get_sigstack(). Move the i387 stuff into get_sigframe(). Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-28x86: signal: add __user annotationHiroshi Shimamoto
Impact: cleanup Add missing __user annotation to the parameter of get_sigframe(). Also change cast type to void __user * of *fpstate. Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-13Merge branch 'x86/core' into perfcounters/coreIngo Molnar
Conflicts: arch/x86/Kconfig arch/x86/kernel/apic.c arch/x86/kernel/setup_percpu.c
2009-02-11x86: merge sys_rt_sigreturn between 32 and 64 bitsH. Peter Anvin
Impact: cleanup With the recent changes in the 32-bit code to make system calls which use struct pt_regs take a pointer, sys_rt_sigreturn() have become identical between 32 and 64 bits, and both are empty wrappers around do_rt_sigreturn(). Remove both wrappers and rename both to sys_rt_sigreturn(). Cc: Brian Gerst <brgerst@gmail.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2009-02-11x86: use regparm(3) for passed-in pt_regs pointerBrian Gerst
Some syscalls need to access the pt_regs structure, either to copy user register state or to modifiy it. This patch adds stubs to load the address of the pt_regs struct into the %eax register, and changes the syscalls to take the pointer as an argument instead of relying on the assumption that the pt_regs structure overlaps the function arguments. Drop the use of regparm(1) due to concern about gcc bugs, and to move in the direction of the eventual removal of regparm(0) for asmlinkage. Signed-off-by: Brian Gerst <brgerst@gmail.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2009-02-11x86: pass in pt_regs pointer for syscalls that need itBrian Gerst
Some syscalls need to access the pt_regs structure, either to copy user register state or to modifiy it. This patch adds stubs to load the address of the pt_regs struct into the %eax register, and changes the syscalls to regparm(1) to receive the pt_regs pointer as the first argument. Signed-off-by: Brian Gerst <brgerst@gmail.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-11Merge commit 'v2.6.29-rc4' into perfcounters/coreIngo Molnar
Conflicts: arch/x86/kernel/setup_percpu.c arch/x86/mm/fault.c drivers/acpi/processor_idle.c kernel/irq/handle.c
2009-02-10x86: add %gs accessors for x86_32Tejun Heo
Impact: cleanup On x86_32, %gs is handled lazily. It's not saved and restored on kernel entry/exit but only when necessary which usually is during task switch but there are few other places. Currently, it's done by calling savesegment() and loadsegment() explicitly. Define get_user_gs(), set_user_gs() and task_user_gs() and use them instead. While at it, clean up register access macros in signal.c. This cleans up code a bit and will help future changes. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-10Merge branch 'x86/uaccess' into core/percpuIngo Molnar
2009-01-23x86: signal: use {get|put}_user_try and catchHiroshi Shimamoto
Impact: use new framework Use {get|put}_user_try, catch, and _ex in arch/x86/kernel/signal.c. Note: this patch contains "WARNING: line over 80 characters", because when introducing new block I insert an indent to avoid mistakes by edit. Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2009-01-21Revert "x86: signal: change type of paramter for sys_rt_sigreturn()"Ingo Molnar
This reverts commit 4217458dafaa57d8e26a46f5d05ab8c53cf64191. Justin Madru bisected this commit, it was causing weird Firefox crashes. The reason is that GCC mis-optimizes (re-uses) the on-stack parameters of the calling frame, which corrupts the syscall return pt_regs state and thus corrupts user-space register state. So we go back to the slightly less clean but more optimization-safe method of getting to pt_regs. Also add a comment to explain this. Resolves: http://bugzilla.kernel.org/show_bug.cgi?id=12505 Reported-and-bisected-by: Justin Madru <jdm64@gawab.com> Tested-by: Justin Madru <jdm64@gawab.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-29Merge branch 'linus' into perfcounters/coreIngo Molnar
Conflicts: fs/exec.c include/linux/init_task.h Simple context conflicts.
2008-12-18x86: signal: move sigframe.h to arch/x86/include/asmHiroshi Shimamoto
Impact: cleanup, move header file Move arch/x86/kernel/sigframe.h to arch/x86/include/asm/sigframe.h. It will be used in arch/x86/ia32/ia32_signal.c. Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-18x86: signal: move ia32 func declarations into arch/x86/kernel/signal.cHiroshi Shimamoto
Impact: cleanup Move declarations of ia32_setup_rt_frame() and ia32_setup_frame() into arch/x86/kernel/signal.c. This is for future use of sigframe.h. Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-16x86: signal: use signal_fault() in sys_sigreturn()Hiroshi Shimamoto
Impact: cleanup Call signal_fault() in error route of sys_sigreturn(). Change log level to KERN_EMERG if current is init. Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-08performance counters: x86 supportIngo Molnar
Implement performance counters for x86 Intel CPUs. It's simplified right now: the PERFMON CPU feature is assumed, which is available in Core2 and later Intel CPUs. The design is flexible to be extended to more CPU types as well. Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-08x86: signal: change type of paramter for sys_rt_sigreturn()Hiroshi Shimamoto
Impact: cleanup on 32-bit Peter pointed this parameter can be changed. Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-26x86: signal: unify signal_{32|64}.cHiroshi Shimamoto
Impact: cleanup Unify signal_{32|64}.c! Mechanic unification - the two files are the same. Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>