- 21 2月, 2012 3 次提交
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由 Linus Torvalds 提交于
This makes us recognize when we try to restore FPU state that matches what we already have in the FPU on this CPU, and avoids the restore entirely if so. To do this, we add two new data fields: - a percpu 'fpu_owner_task' variable that gets written any time we update the "has_fpu" field, and thus acts as a kind of back-pointer to the task that owns the CPU. The exception is when we save the FPU state as part of a context switch - if the save can keep the FPU state around, we leave the 'fpu_owner_task' variable pointing at the task whose FP state still remains on the CPU. - a per-thread 'last_cpu' field, that indicates which CPU that thread used its FPU on last. We update this on every context switch (writing an invalid CPU number if the last context switch didn't leave the FPU in a lazily usable state), so we know that *that* thread has done nothing else with the FPU since. These two fields together can be used when next switching back to the task to see if the CPU still matches: if 'fpu_owner_task' matches the task we are switching to, we know that no other task (or kernel FPU usage) touched the FPU on this CPU in the meantime, and if the current CPU number matches the 'last_cpu' field, we know that this thread did no other FP work on any other CPU, so the FPU state on the CPU must match what was saved on last context switch. In that case, we can avoid the 'f[x]rstor' entirely, and just clear the CR0.TS bit. Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Linus Torvalds 提交于
This inlines what is usually just a couple of instructions, but more importantly it also fixes the theoretical error case (can that FPU restore really ever fail? Maybe we should remove the checking). We can't start sending signals from within the scheduler, we're much too deep in the kernel and are holding the runqueue lock etc. So don't bother even trying. Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Linus Torvalds 提交于
This makes sure we clear the FPU usage counter for newly created tasks, just so that we start off in a known state (for example, don't try to preload the FPU state on the first task switch etc). It also fixes a thinko in when we increment the fpu_counter at task switch time, introduced by commit 34ddc81a ("i387: re-introduce FPU state preloading at context switch time"). We should increment the *new* task fpu_counter, not the old task, and only if we decide to use that state (whether lazily or preloaded). Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 19 2月, 2012 2 次提交
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由 Linus Torvalds 提交于
After all the FPU state cleanups and finally finding the problem that caused all our FPU save/restore problems, this re-introduces the preloading of FPU state that was removed in commit b3b0870e ("i387: do not preload FPU state at task switch time"). However, instead of simply reverting the removal, this reimplements preloading with several fixes, most notably - properly abstracted as a true FPU state switch, rather than as open-coded save and restore with various hacks. In particular, implementing it as a proper FPU state switch allows us to optimize the CR0.TS flag accesses: there is no reason to set the TS bit only to then almost immediately clear it again. CR0 accesses are quite slow and expensive, don't flip the bit back and forth for no good reason. - Make sure that the same model works for both x86-32 and x86-64, so that there are no gratuitous differences between the two due to the way they save and restore segment state differently due to architectural differences that really don't matter to the FPU state. - Avoid exposing the "preload" state to the context switch routines, and in particular allow the concept of lazy state restore: if nothing else has used the FPU in the meantime, and the process is still on the same CPU, we can avoid restoring state from memory entirely, just re-expose the state that is still in the FPU unit. That optimized lazy restore isn't actually implemented here, but the infrastructure is set up for it. Of course, older CPU's that use 'fnsave' to save the state cannot take advantage of this, since the state saving also trashes the state. In other words, there is now an actual _design_ to the FPU state saving, rather than just random historical baggage. Hopefully it's easier to follow as a result. Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Linus Torvalds 提交于
This moves the bit that indicates whether a thread has ownership of the FPU from the TS_USEDFPU bit in thread_info->status to a word of its own (called 'has_fpu') in task_struct->thread.has_fpu. This fixes two independent bugs at the same time: - changing 'thread_info->status' from the scheduler causes nasty problems for the other users of that variable, since it is defined to be thread-synchronous (that's what the "TS_" part of the naming was supposed to indicate). So perfectly valid code could (and did) do ti->status |= TS_RESTORE_SIGMASK; and the compiler was free to do that as separate load, or and store instructions. Which can cause problems with preemption, since a task switch could happen in between, and change the TS_USEDFPU bit. The change to TS_USEDFPU would be overwritten by the final store. In practice, this seldom happened, though, because the 'status' field was seldom used more than once, so gcc would generally tend to generate code that used a read-modify-write instruction and thus happened to avoid this problem - RMW instructions are naturally low fat and preemption-safe. - On x86-32, the current_thread_info() pointer would, during interrupts and softirqs, point to a *copy* of the real thread_info, because x86-32 uses %esp to calculate the thread_info address, and thus the separate irq (and softirq) stacks would cause these kinds of odd thread_info copy aliases. This is normally not a problem, since interrupts aren't supposed to look at thread information anyway (what thread is running at interrupt time really isn't very well-defined), but it confused the heck out of irq_fpu_usable() and the code that tried to squirrel away the FPU state. (It also caused untold confusion for us poor kernel developers). It also turns out that using 'task_struct' is actually much more natural for most of the call sites that care about the FPU state, since they tend to work with the task struct for other reasons anyway (ie scheduling). And the FPU data that we are going to save/restore is found there too. Thanks to Arjan Van De Ven <arjan@linux.intel.com> for pointing us to the %esp issue. Cc: Arjan van de Ven <arjan@linux.intel.com> Reported-and-tested-by: NRaphael Prevost <raphael@buro.asia> Acked-and-tested-by: NSuresh Siddha <suresh.b.siddha@intel.com> Tested-by: NPeter Anvin <hpa@zytor.com> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 17 2月, 2012 4 次提交
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由 Linus Torvalds 提交于
The AMD K7/K8 CPUs don't save/restore FDP/FIP/FOP unless an exception is pending. In order to not leak FIP state from one process to another, we need to do a floating point load after the fxsave of the old process, and before the fxrstor of the new FPU state. That resets the state to the (uninteresting) kernel load, rather than some potentially sensitive user information. We used to do this directly after the FPU state save, but that is actually very inconvenient, since it (a) corrupts what is potentially perfectly good FPU state that we might want to lazy avoid restoring later and (b) on x86-64 it resulted in a very annoying ordering constraint, where "__unlazy_fpu()" in the task switch needs to be delayed until after the DS segment has been reloaded just to get the new DS value. Coupling it to the fxrstor instead of the fxsave automatically avoids both of these issues, and also ensures that we only do it when actually necessary (the FP state after a save may never actually get used). It's simply a much more natural place for the leaked state cleanup. Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Linus Torvalds 提交于
Yes, taking the trap to re-load the FPU/MMX state is expensive, but so is spending several days looking for a bug in the state save/restore code. And the preload code has some rather subtle interactions with both paravirtualization support and segment state restore, so it's not nearly as simple as it should be. Also, now that we no longer necessarily depend on a single bit (ie TS_USEDFPU) for keeping track of the state of the FPU, we migth be able to do better. If we are really switching between two processes that keep touching the FP state, save/restore is inevitable, but in the case of having one process that does most of the FPU usage, we may actually be able to do much better than the preloading. In particular, we may be able to keep track of which CPU the process ran on last, and also per CPU keep track of which process' FP state that CPU has. For modern CPU's that don't destroy the FPU contents on save time, that would allow us to do a lazy restore by just re-enabling the existing FPU state - with no restore cost at all! Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Linus Torvalds 提交于
This creates three helper functions that do the TS_USEDFPU accesses, and makes everybody that used to do it by hand use those helpers instead. In addition, there's a couple of helper functions for the "change both CR0.TS and TS_USEDFPU at the same time" case, and the places that do that together have been changed to use those. That means that we have fewer random places that open-code this situation. The intent is partly to clarify the code without actually changing any semantics yet (since we clearly still have some hard to reproduce bug in this area), but also to make it much easier to use another approach entirely to caching the CR0.TS bit for software accesses. Right now we use a bit in the thread-info 'status' variable (this patch does not change that), but we might want to make it a full field of its own or even make it a per-cpu variable. Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Linus Torvalds 提交于
Commit 5b1cbac3 ("i387: make irq_fpu_usable() tests more robust") added a sanity check to the #NM handler to verify that we never cause the "Device Not Available" exception in kernel mode. However, that check actually pinpointed a (fundamental) race where we do cause that exception as part of the signal stack FPU state save/restore code. Because we use the floating point instructions themselves to save and restore state directly from user mode, we cannot do that atomically with testing the TS_USEDFPU bit: the user mode access itself may cause a page fault, which causes a task switch, which saves and restores the FP/MMX state from the kernel buffers. This kind of "recursive" FP state save is fine per se, but it means that when the signal stack save/restore gets restarted, it will now take the '#NM' exception we originally tried to avoid. With preemption this can happen even without the page fault - but because of the user access, we cannot just disable preemption around the save/restore instruction. There are various ways to solve this, including using the "enable/disable_page_fault()" helpers to not allow page faults at all during the sequence, and fall back to copying things by hand without the use of the native FP state save/restore instructions. However, the simplest thing to do is to just allow the #NM from kernel space, but fix the race in setting and clearing CR0.TS that this all exposed: the TS bit changes and the TS_USEDFPU bit absolutely have to be atomic wrt scheduling, so while the actual state save/restore can be interrupted and restarted, the act of actually clearing/setting CR0.TS and the TS_USEDFPU bit together must not. Instead of just adding random "preempt_disable/enable()" calls to what is already excessively ugly code, this introduces some helper functions that mostly mirror the "kernel_fpu_begin/end()" functionality, just for the user state instead. Those helper functions should probably eventually replace the other ad-hoc CR0.TS and TS_USEDFPU tests too, but I'll need to think about it some more: the task switching functionality in particular needs to expose the difference between the 'prev' and 'next' threads, while the new helper functions intentionally were written to only work with 'current'. Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 14 2月, 2012 2 次提交
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由 Linus Torvalds 提交于
Some code - especially the crypto layer - wants to use the x86 FP/MMX/AVX register set in what may be interrupt (typically softirq) context. That *can* be ok, but the tests for when it was ok were somewhat suspect. We cannot touch the thread-specific status bits either, so we'd better check that we're not going to try to save FP state or anything like that. Now, it may be that the TS bit is always cleared *before* we set the USEDFPU bit (and only set when we had already cleared the USEDFP before), so the TS bit test may actually have been sufficient, but it certainly was not obviously so. So this explicitly verifies that we will not touch the TS_USEDFPU bit, and adds a few related sanity-checks. Because it seems that somehow AES-NI is corrupting user FP state. The cause is not clear, and this patch doesn't fix it, but while debugging it I really wanted the code to be more obviously correct and robust. Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Linus Torvalds 提交于
It was marked asmlinkage for some really old and stale legacy reasons. Fix that and the equally stale comment. Noticed when debugging the irq_fpu_usable() bugs. Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 07 2月, 2012 1 次提交
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由 Stephane Eranian 提交于
The following patch fixes a bug introduced by the following commit: e050e3f0 ("perf: Fix broken interrupt rate throttling") The patch caused the following warning to pop up depending on the sampling frequency adjustments: ------------[ cut here ]------------ WARNING: at arch/x86/kernel/cpu/perf_event.c:995 x86_pmu_start+0x79/0xd4() It was caused by the following call sequence: perf_adjust_freq_unthr_context.part() { stop() if (delta > 0) { perf_adjust_period() { if (period > 8*...) { stop() ... start() } } } start() } Which caused a double start and a double stop, thus triggering the assert in x86_pmu_start(). The patch fixes the problem by avoiding the double calls. We pass a new argument to perf_adjust_period() to indicate whether or not the event is already stopped. We can't just remove the start/stop from that function because it's called from __perf_event_overflow where the event needs to be reloaded via a stop/start back-toback call. The patch reintroduces the assertion in x86_pmu_start() which was removed by commit: 84f2b9b2 ("perf: Remove deprecated WARN_ON_ONCE()") In this second version, we've added calls to disable/enable PMU during unthrottling or frequency adjustment based on bug report of spurious NMI interrupts from Eric Dumazet. Reported-and-tested-by: NEric Dumazet <eric.dumazet@gmail.com> Signed-off-by: NStephane Eranian <eranian@google.com> Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> Cc: markus@trippelsdorf.de Cc: paulus@samba.org Link: http://lkml.kernel.org/r/20120207133956.GA4932@quad [ Minor edits to the changelog and to the code ] Signed-off-by: NIngo Molnar <mingo@elte.hu>
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- 03 2月, 2012 1 次提交
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由 Stephane Eranian 提交于
With the new throttling/unthrottling code introduced with commit: e050e3f0 ("perf: Fix broken interrupt rate throttling") we occasionally hit two WARN_ON_ONCE() checks in: - intel_pmu_pebs_enable() - intel_pmu_lbr_enable() - x86_pmu_start() The assertions are no longer problematic. There is a valid path where they can trigger but it is harmless. The assertion can be triggered with: $ perf record -e instructions:pp .... Leading to paths: intel_pmu_pebs_enable intel_pmu_enable_event x86_perf_event_set_period x86_pmu_start perf_adjust_freq_unthr_context perf_event_task_tick scheduler_tick And: intel_pmu_lbr_enable intel_pmu_enable_event x86_perf_event_set_period x86_pmu_start perf_adjust_freq_unthr_context. perf_event_task_tick scheduler_tick cpuc->enabled is always on because when we get to perf_adjust_freq_unthr_context() the PMU is not totally disabled. Furthermore when we need to adjust a period, we only stop the event we need to change and not the entire PMU. Thus, when we re-enable, cpuc->enabled is already set. Note that when we stop the event, both pebs and lbr are stopped if necessary (and possible). Signed-off-by: NStephane Eranian <eranian@google.com> Cc: peterz@infradead.org Link: http://lkml.kernel.org/r/20120202110401.GA30911@quadSigned-off-by: NIngo Molnar <mingo@elte.hu>
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- 30 1月, 2012 2 次提交
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由 Michael D Labriola 提交于
This commit removes the reboot quirk originally added by commit e19e074b ("x86: Fix reboot problem on VersaLogic Menlow boards"). Testing with a VersaLogic Ocelot (VL-EPMs-21a rev 1.00 w/ BIOS 6.5.102) revealed the following regarding the reboot hang problem: - v2.6.37 reboot=bios was needed. - v2.6.38-rc1: behavior changed, reboot=acpi is needed, reboot=kbd and reboot=bios results in system hang. - v2.6.38: VersaLogic patch (e19e074b "x86: Fix reboot problem on VersaLogic Menlow boards") was applied prior to v2.6.38-rc7. This patch sets a quirk for VersaLogic Menlow boards that forces the use of reboot=bios, which doesn't work anymore. - v3.2: It seems that commit 660e34ce ("x86: Reorder reboot method preferences") changed the default reboot method to acpi prior to v3.0-rc1, which means the default behavior is appropriate for the Ocelot. No VersaLogic quirk is required. The Ocelot board used for testing can successfully reboot w/out having to pass any reboot= arguments for all 3 current versions of the BIOS. Signed-off-by: NMichael D Labriola <michael.d.labriola@gmail.com> Cc: Matthew Garrett <mjg@redhat.com> Cc: Michael D Labriola <mlabriol@gdeb.com> Cc: Kushal Koolwal <kushalkoolwal@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/87vcnub9hu.fsf@gmail.comSigned-off-by: NIngo Molnar <mingo@elte.hu>
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由 Michael D Labriola 提交于
Skip DMI checks for vendor specific reboot quirks if the user passed in a reboot= arg on the command line - we should never override user choices. Signed-off-by: NMichael D Labriola <michael.d.labriola@gmail.com> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Michael D Labriola <mlabriol@gdeb.com> Cc: Matthew Garrett <mjg@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/87wr8ab9od.fsf@gmail.comSigned-off-by: NIngo Molnar <mingo@elte.hu>
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- 28 1月, 2012 1 次提交
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由 Dan Carpenter 提交于
Smatch complains that we have some inconsistent NULL checking. If "task" were NULL then it would lead to a NULL dereference later. We can remove this test because earlier on in the function we have: if (!task) task = current; Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com> Acked-by: NFrederic Weisbecker <fweisbec@gmail.com> Cc: Namhyung Kim <namhyung@gmail.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Clemens Ladisch <clemens@ladisch.de> Link: http://lkml.kernel.org/r/20120128105246.GA25092@elgon.mountainSigned-off-by: NIngo Molnar <mingo@elte.hu>
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- 27 1月, 2012 1 次提交
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由 Prarit Bhargava 提交于
rsyslog will display KERN_EMERG messages on a connected terminal. However, these messages are useless/undecipherable for a general user. For example, after a softlockup we get: Message from syslogd@intel-s3e37-04 at Jan 25 14:18:06 ... kernel:Stack: Message from syslogd@intel-s3e37-04 at Jan 25 14:18:06 ... kernel:Call Trace: Message from syslogd@intel-s3e37-04 at Jan 25 14:18:06 ... kernel:Code: ff ff a8 08 75 25 31 d2 48 8d 86 38 e0 ff ff 48 89 d1 0f 01 c8 0f ae f0 48 8b 86 38 e0 ff ff a8 08 75 08 b1 01 4c 89 e0 0f 01 c9 <e8> ea 69 dd ff 4c 29 e8 48 89 c7 e8 0f bc da ff 49 89 c4 49 89 This happens because the printk levels for these messages are incorrect. Only an informational message should be displayed on a terminal. I modified the printk levels for various messages in the kernel and tested the output by using the drivers/misc/lkdtm.c kernel modules (ie, softlockups, panics, hard lockups, etc.) and confirmed that the console output was still the same and that the output to the terminals was correct. For example, in the case of a softlockup we now see the much more informative: Message from syslogd@intel-s3e37-04 at Jan 25 10:18:06 ... BUG: soft lockup - CPU4 stuck for 60s! instead of the above confusing messages. AFAICT, the messages no longer have to be KERN_EMERG. In the most important case of a panic we set console_verbose(). As for the other less severe cases the correct data is output to the console and /var/log/messages. Successfully tested by me using the drivers/misc/lkdtm.c module. Signed-off-by: NPrarit Bhargava <prarit@redhat.com> Cc: dzickus@redhat.com Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Link: http://lkml.kernel.org/r/1327586134-11926-1-git-send-email-prarit@redhat.comSigned-off-by: NIngo Molnar <mingo@elte.hu>
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- 26 1月, 2012 1 次提交
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由 Andreas Herrmann 提交于
We've decided to provide CPU family specific container files (starting with CPU family 15h). E.g. for family 15h we have to load microcode_amd_fam15h.bin instead of microcode_amd.bin Rationale is that starting with family 15h patch size is larger than 2KB which was hard coded as maximum patch size in various microcode loaders (not just Linux). Container files which include patches larger than 2KB cause different kinds of trouble with such old patch loaders. Thus we have to ensure that the default container file provides only patches with size less than 2KB. Signed-off-by: NAndreas Herrmann <andreas.herrmann3@amd.com> Cc: Borislav Petkov <borislav.petkov@amd.com> Cc: <stable@kernel.org> Link: http://lkml.kernel.org/r/20120120164412.GD24508@alberich.amd.com [ documented the naming convention and tidied the code a bit. ] Signed-off-by: NIngo Molnar <mingo@elte.hu>
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- 18 1月, 2012 4 次提交
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由 Al Viro 提交于
JONGMAN HEO reports: With current linus git (commit a25a2b84), I got following build error, arch/x86/kernel/vm86_32.c: In function 'do_sys_vm86': arch/x86/kernel/vm86_32.c:340: error: implicit declaration of function '__audit_syscall_exit' make[3]: *** [arch/x86/kernel/vm86_32.o] Error 1 OK, I can reproduce it (32bit allmodconfig with AUDIT=y, AUDITSYSCALL=n) It's due to commit d7e7528b: "Audit: push audit success and retcode into arch ptrace.h". Reported-by: NJONGMAN HEO <jongman.heo@samsung.com> Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Linus Torvalds 提交于
pit_expect_msb() returns success wrongly in the below SMI scenario: a. pit_verify_msb() has not yet seen the MSB transition. b. we are close to the MSB transition though and got a SMI immediately after returning from pit_verify_msb() which didn't see the MSB transition. PIT MSB transition has happened somewhere during SMI execution. c. returned from SMI and we noted down the 'tsc', saw the pit MSB change now and exited the loop to calculate 'deltatsc'. Instead of noting the TSC at the MSB transition, we are way off because of the SMI. And as the SMI happened between the pit_verify_msb() and before the 'tsc' is recorded in the for loop, 'delattsc' (d1/d2 in quick_pit_calibrate()) will be small and quick_pit_calibrate() will not notice this error. Depending on whether SMI disturbance happens while computing d1 or d2, we will see the TSC calibrated value smaller or bigger than the expected value. As a result, in a cluster we were seeing a variation of approximately +/- 20MHz in the calibrated values, resulting in NTP failures. [ As far as the SMI source is concerned, this is a periodic SMI that gets disabled after ACPI is enabled by the OS. But the TSC calibration happens before the ACPI is enabled. ] To address this, change pit_expect_msb() so that - the 'tsc' is the TSC in between the two reads that read the MSB change from the PIT (same as before) - the 'delta' is the difference in TSC from *before* the MSB changed to *after* the MSB changed. Now the delta is twice as big as before (it covers four PIT accesses, roughly 4us) and quick_pit_calibrate() will loop a bit longer to get the calibrated value with in the 500ppm precision. As the delta (d1/d2) covers four PIT accesses, actual calibrated result might be closer to 250ppm precision. As the loop now takes longer to stabilize, double MAX_QUICK_PIT_MS to 50. SMI disturbance will showup as much larger delta's and the loop will take longer than usual for the result to be with in the accepted precision. Or will fallback to slow PIT calibration if it takes more than 50msec. Also while we are at this, remove the calibration correction that aims to get the result to the middle of the error bars. We really don't know which direction to correct into, so remove it. Reported-and-tested-by: NSuresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org> Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com> Link: http://lkml.kernel.org/r/1326843337.5291.4.camel@sbsiddha-mobl2Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
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由 Eric Paris 提交于
Every arch calls: if (unlikely(current->audit_context)) audit_syscall_entry() which requires knowledge about audit (the existance of audit_context) in the arch code. Just do it all in static inline in audit.h so that arch's can remain blissfully ignorant. Signed-off-by: NEric Paris <eparis@redhat.com>
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由 Eric Paris 提交于
The audit system previously expected arches calling to audit_syscall_exit to supply as arguments if the syscall was a success and what the return code was. Audit also provides a helper AUDITSC_RESULT which was supposed to simplify things by converting from negative retcodes to an audit internal magic value stating success or failure. This helper was wrong and could indicate that a valid pointer returned to userspace was a failed syscall. The fix is to fix the layering foolishness. We now pass audit_syscall_exit a struct pt_reg and it in turns calls back into arch code to collect the return value and to determine if the syscall was a success or failure. We also define a generic is_syscall_success() macro which determines success/failure based on if the value is < -MAX_ERRNO. This works for arches like x86 which do not use a separate mechanism to indicate syscall failure. We make both the is_syscall_success() and regs_return_value() static inlines instead of macros. The reason is because the audit function must take a void* for the regs. (uml calls theirs struct uml_pt_regs instead of just struct pt_regs so audit_syscall_exit can't take a struct pt_regs). Since the audit function takes a void* we need to use static inlines to cast it back to the arch correct structure to dereference it. The other major change is that on some arches, like ia64, MIPS and ppc, we change regs_return_value() to give us the negative value on syscall failure. THE only other user of this macro, kretprobe_example.c, won't notice and it makes the value signed consistently for the audit functions across all archs. In arch/sh/kernel/ptrace_64.c I see that we were using regs[9] in the old audit code as the return value. But the ptrace_64.h code defined the macro regs_return_value() as regs[3]. I have no idea which one is correct, but this patch now uses the regs_return_value() function, so it now uses regs[3]. For powerpc we previously used regs->result but now use the regs_return_value() function which uses regs->gprs[3]. regs->gprs[3] is always positive so the regs_return_value(), much like ia64 makes it negative before calling the audit code when appropriate. Signed-off-by: NEric Paris <eparis@redhat.com> Acked-by: H. Peter Anvin <hpa@zytor.com> [for x86 portion] Acked-by: Tony Luck <tony.luck@intel.com> [for ia64] Acked-by: Richard Weinberger <richard@nod.at> [for uml] Acked-by: David S. Miller <davem@davemloft.net> [for sparc] Acked-by: Ralf Baechle <ralf@linux-mips.org> [for mips] Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> [for ppc]
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- 17 1月, 2012 2 次提交
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由 Huang Ying 提交于
Some firmware will access memory in ACPI NVS region via APEI. That is, instructions in APEI ERST/EINJ table will read/write ACPI NVS region. The original resource conflict checking in APEI code will check memory/ioport accessed by APEI via general resource management mechanism. But ACPI NVS region is marked as busy already, so that the false resource conflict will prevent APEI ERST/EINJ to work. To fix this, this patch record ACPI NVS regions, so that we can avoid request resources for memory region inside it. Signed-off-by: NHuang Ying <ying.huang@intel.com> Signed-off-by: NLen Brown <len.brown@intel.com>
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由 Greg Kroah-Hartman 提交于
When suspending, there was a large list of warnings going something like: Device 'machinecheck1' does not have a release() function, it is broken and must be fixed This patch turns the static mce_devices into dynamically allocated, and properly frees them when they are removed from the system. It solves the warning messages on my laptop here. Reported-by: N"Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com> Reported-by: NLinus Torvalds <torvalds@linux-foundation.org> Tested-by: NDjalal Harouni <tixxdz@opendz.org> Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Tony Luck <tony.luck@intel.com> Cc: Borislav Petkov <bp@amd64.org> Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 14 1月, 2012 1 次提交
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由 Srivatsa S. Bhat 提交于
Commit 8a25a2fd ("cpu: convert 'cpu' and 'machinecheck' sysdev_class to a regular subsystem") changed how things are dealt with in the MCE subsystem. Some of the things that got broken due to this are CPU hotplug and suspend/hibernate. MCE uses per_cpu allocations of struct device. So, when a CPU goes offline and comes back online, in order to ensure that we start from a clean slate with respect to the MCE subsystem, zero out the entire per_cpu device structure to 0 before using it. Signed-off-by: NSrivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 13 1月, 2012 1 次提交
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由 Rusty Russell 提交于
module_param(bool) used to counter-intuitively take an int. In fddd5201 (mid-2009) we allowed bool or int/unsigned int using a messy trick. It's time to remove the int/unsigned int option. For this version it'll simply give a warning, but it'll break next kernel version. Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
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- 11 1月, 2012 1 次提交
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由 Matt Fleming 提交于
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: NMatt Fleming <matt.fleming@intel.com> Signed-off-by: NOleg 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: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 08 1月, 2012 1 次提交
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由 Jack Steiner 提交于
SGI UV systems print a message during boot: UV: Found <num> blades Due to packaging changes, the blade count is not accurate for on the next generation of the platform. This patch corrects the count. Signed-off-by: NJack Steiner <steiner@sgi.com> Cc: <stable@kernel.org> Link: http://lkml.kernel.org/r/20120106191900.GA19772@sgi.comSigned-off-by: NIngo Molnar <mingo@elte.hu>
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- 07 1月, 2012 3 次提交
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由 Don Zickus 提交于
It was brought to my attention that my x86 change to use NMI in the reboot path broke Intel Nehalem and Westmere boxes when using kexec. I realized I had mistyped the if statement in commit 3603a251 and stuck the ')' in the wrong spot. Putting it in the right spot fixes kexec again. Doh. Reported-by: NYinghai Lu <yinghai@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: NDon Zickus <dzickus@redhat.com> Link: http://lkml.kernel.org/r/1325866671-9797-1-git-send-email-dzickus@redhat.comSigned-off-by: NIngo Molnar <mingo@elte.hu>
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由 Konrad Rzeszutek Wilk 提交于
The MSI restore function will become a function pointer in an x86_msi_ops struct. It defaults to the implementation in the io_apic.c and msi.c. We piggyback on the indirection mechanism introduced by "x86: Introduce x86_msi_ops". Cc: x86@kernel.org Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: linux-pci@vger.kernel.org Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
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由 Bjorn Helgaas 提交于
This factors out the AMD native MMCONFIG discovery so we can use it outside amd_bus.c. amd_bus.c reads AMD MSRs so it can remove the MMCONFIG area from the PCI resources. We may also need the MMCONFIG information to work around BIOS defects in the ACPI MCFG table. Cc: Borislav Petkov <borislav.petkov@amd.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: stable@kernel.org # 2.6.34+ Signed-off-by: NBjorn Helgaas <bhelgaas@google.com> Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
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- 04 1月, 2012 1 次提交
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由 Al Viro 提交于
both callers of device_get_devnode() are only interested in lower 16bits and nobody tries to return anything wider than 16bit anyway. Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
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- 27 12月, 2011 1 次提交
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由 Chris Wright 提交于
This has not been used for some years now. It's time to remove it. Signed-off-by: NChris Wright <chrisw@redhat.com> Signed-off-by: NAvi Kivity <avi@redhat.com>
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- 24 12月, 2011 6 次提交
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由 Suresh Siddha 提交于
If the x2apic mode is disabled for reasons like interrupt-remapping not available etc, then we need to skip the logical cpu bringup of apic-id's >= 255. Otherwise as the platform is in xapic mode, init/startup IPI's will consider only the low 8-bits and there is a possibility of re-sending init/startup IPI's to the logical cpu that is already online. This will avoid potential reboots/unpredictable behavior etc. Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com> Link: http://lkml.kernel.org/r/20111222014632.702932458@sbsiddha-desk.sc.intel.comSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>
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由 Yinghai Lu 提交于
Currently "nox2apic" boot parameter was not enabling x2apic mode if the cpu, kernel are all capable of enabling x2apic mode and the OS handover happened in xapic mode. However If the bios enabled x2apic prior to OS handover, using "nox2apic" boot parameter had no effect. If the boot cpu's apicid is < 255, enable "nox2apic" boot parameter to disable the x2apic mode setup by the bios. This will enable the kernel to fallback to xapic mode and bringup only the cpu's which has apic-id < 255. -v2: fix patch error and two compiling warning make disable_x2apic to be __init Signed-off-by: NYinghai Lu <yinghai@kernel.org> Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com> Link: http://lkml.kernel.org/r/CAE9FiQUeB-3uxJAMiHsz=uPWoFv5Hg1pVepz7aU6YtqOxMC-=Q@mail.gmail.comSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>
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由 Yinghai Lu 提交于
On some of the recent Intel SNB platforms, by default bios is pre-enabling x2apic mode in the cpu with out setting up interrupt-remapping. This case was resulting in the kernel to panic as the cpu is already in x2apic mode but the OS was not able to enable interrupt-remapping (which is a pre-req for using x2apic capability). On these platforms all the apic-ids are < 255 and the kernel can fallback to xapic mode if the bios has not enabled interrupt-remapping (which is mostly the case if the bios has not exported interrupt-remapping tables to the OS). Reported-by: NBerck E. Nash <flyboy@gmail.com> Signed-off-by: NYinghai Lu <yinghai@kernel.org> Link: http://lkml.kernel.org/r/20111222014632.600418637@sbsiddha-desk.sc.intel.comSigned-off-by: NSuresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>
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由 Yinghai Lu 提交于
If the x2apic feature is not present (either the cpu is not capable of it or the user has disabled the feature using boot-parameter etc), ignore the x2apic MADT and SRAT entries provided by the ACPI tables. Signed-off-by: NYinghai Lu <yinghai@kernel.org> Link: http://lkml.kernel.org/r/20111222014632.540896503@sbsiddha-desk.sc.intel.comSigned-off-by: NSuresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>
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由 Yinghai Lu 提交于
Currently we start with the default apic_flat mode and switch to some other apic model depending on the apic drivers acpi_madt_oem_check() routines and later followed by the apic drivers probe() routines. Once we selected non flat mode there was no case where we fall back to flat mode again. Upcoming changes allow bios-enabled x2apic mode to be disabled by the OS if interrupt-remapping etc is not setup properly by the bios. We now has a case for the apic to fall back to legacy flat mode during apic driver probe() seqeuence. Add a simple flat_probe() which allows the apic_flat mode to be the last fallback option. Signed-off-by: NYinghai Lu <yinghai@kernel.org> Link: http://lkml.kernel.org/r/20111222014632.484984298@sbsiddha-desk.sc.intel.comSigned-off-by: NSuresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>
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由 Robert Richter 提交于
Use raw_spin_unlock_irqrestore() as equivalent to raw_spin_lock_irqsave(). Signed-off-by: NRobert Richter <robert.richter@amd.com> Cc: Stephane Eranian <eranian@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1324646665-13334-1-git-send-email-robert.richter@amd.comSigned-off-by: NIngo Molnar <mingo@elte.hu>
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- 22 12月, 2011 1 次提交
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由 Kay Sievers 提交于
The sysdev.h file should not be needed by any in-kernel code, so remove the .h file from these random files that seem to still want to include it. The sysdev code will be going away soon, so this include needs to be removed no matter what. Cc: Jiandong Zheng <jdzheng@broadcom.com> Cc: Scott Branden <sbranden@broadcom.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Kukjin Kim <kgene.kim@samsung.com> Cc: David Brown <davidb@codeaurora.org> Cc: Daniel Walker <dwalker@fifo99.com> Cc: Bryan Huntsman <bryanh@codeaurora.org> Cc: Ben Dooks <ben-linux@fluff.org> Cc: Wan ZongShun <mcuos.com@gmail.com> Cc: Haavard Skinnemoen <hskinnemoen@gmail.com> Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Cc: "Venkatesh Pallipadi Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Grant Likely <grant.likely@secretlab.ca> Cc: Richard Purdie <rpurdie@rpsys.net> Cc: Matthew Garrett <mjg@redhat.com> Signed-off-by: NKay Sievers <kay.sievers@vrfy.org>
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