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| * x86-32: Fix endless loop when processing signals for kernel tasksDmitry Adamushko2012-04-021-7/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 29a2e2836ff9ea65a603c89df217f4198973a74f upstream. The problem occurs on !CONFIG_VM86 kernels [1] when a kernel-mode task returns from a system call with a pending signal. A real-life scenario is a child of 'khelper' returning from a failed kernel_execve() in ____call_usermodehelper() [ kernel/kmod.c ]. kernel_execve() fails due to a pending SIGKILL, which is the result of "kill -9 -1" (at least, busybox's init does it upon reboot). The loop is as follows: * syscall_exit_work: - work_pending: // start_of_the_loop - work_notify_sig: - do_notify_resume() - do_signal() - if (!user_mode(regs)) return; - resume_userspace // TIF_SIGPENDING is still set - work_pending // so we call work_pending => goto // start_of_the_loop More information can be found in another LKML thread: http://www.serverphorums.com/read.php?12,457826 [1] the problem was also seen on MIPS. Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com> Link: http://lkml.kernel.org/r/1332448765.2299.68.camel@dimm Cc: Oleg Nesterov <oleg@redhat.com> Cc: Roland McGrath <roland@hack.frob.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * mm: thp: fix pmd_bad() triggering in code paths holding mmap_sem read modeAndrea Arcangeli2012-04-021-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 1a5a9906d4e8d1976b701f889d8f35d54b928f25 upstream. In some cases it may happen that pmd_none_or_clear_bad() is called with the mmap_sem hold in read mode. In those cases the huge page faults can allocate hugepmds under pmd_none_or_clear_bad() and that can trigger a false positive from pmd_bad() that will not like to see a pmd materializing as trans huge. It's not khugepaged causing the problem, khugepaged holds the mmap_sem in write mode (and all those sites must hold the mmap_sem in read mode to prevent pagetables to go away from under them, during code review it seems vm86 mode on 32bit kernels requires that too unless it's restricted to 1 thread per process or UP builds). The race is only with the huge pagefaults that can convert a pmd_none() into a pmd_trans_huge(). Effectively all these pmd_none_or_clear_bad() sites running with mmap_sem in read mode are somewhat speculative with the page faults, and the result is always undefined when they run simultaneously. This is probably why it wasn't common to run into this. For example if the madvise(MADV_DONTNEED) runs zap_page_range() shortly before the page fault, the hugepage will not be zapped, if the page fault runs first it will be zapped. Altering pmd_bad() not to error out if it finds hugepmds won't be enough to fix this, because zap_pmd_range would then proceed to call zap_pte_range (which would be incorrect if the pmd become a pmd_trans_huge()). The simplest way to fix this is to read the pmd in the local stack (regardless of what we read, no need of actual CPU barriers, only compiler barrier needed), and be sure it is not changing under the code that computes its value. Even if the real pmd is changing under the value we hold on the stack, we don't care. If we actually end up in zap_pte_range it means the pmd was not none already and it was not huge, and it can't become huge from under us (khugepaged locking explained above). All we need is to enforce that there is no way anymore that in a code path like below, pmd_trans_huge can be false, but pmd_none_or_clear_bad can run into a hugepmd. The overhead of a barrier() is just a compiler tweak and should not be measurable (I only added it for THP builds). I don't exclude different compiler versions may have prevented the race too by caching the value of *pmd on the stack (that hasn't been verified, but it wouldn't be impossible considering pmd_none_or_clear_bad, pmd_bad, pmd_trans_huge, pmd_none are all inlines and there's no external function called in between pmd_trans_huge and pmd_none_or_clear_bad). if (pmd_trans_huge(*pmd)) { if (next-addr != HPAGE_PMD_SIZE) { VM_BUG_ON(!rwsem_is_locked(&tlb->mm->mmap_sem)); split_huge_page_pmd(vma->vm_mm, pmd); } else if (zap_huge_pmd(tlb, vma, pmd, addr)) continue; /* fall through */ } if (pmd_none_or_clear_bad(pmd)) Because this race condition could be exercised without special privileges this was reported in CVE-2012-1179. The race was identified and fully explained by Ulrich who debugged it. I'm quoting his accurate explanation below, for reference. ====== start quote ======= mapcount 0 page_mapcount 1 kernel BUG at mm/huge_memory.c:1384! At some point prior to the panic, a "bad pmd ..." message similar to the following is logged on the console: mm/memory.c:145: bad pmd ffff8800376e1f98(80000000314000e7). The "bad pmd ..." message is logged by pmd_clear_bad() before it clears the page's PMD table entry. 143 void pmd_clear_bad(pmd_t *pmd) 144 { -> 145 pmd_ERROR(*pmd); 146 pmd_clear(pmd); 147 } After the PMD table entry has been cleared, there is an inconsistency between the actual number of PMD table entries that are mapping the page and the page's map count (_mapcount field in struct page). When the page is subsequently reclaimed, __split_huge_page() detects this inconsistency. 1381 if (mapcount != page_mapcount(page)) 1382 printk(KERN_ERR "mapcount %d page_mapcount %d\n", 1383 mapcount, page_mapcount(page)); -> 1384 BUG_ON(mapcount != page_mapcount(page)); The root cause of the problem is a race of two threads in a multithreaded process. Thread B incurs a page fault on a virtual address that has never been accessed (PMD entry is zero) while Thread A is executing an madvise() system call on a virtual address within the same 2 MB (huge page) range. virtual address space .---------------------. | | | | .-|---------------------| | | | | | |<-- B(fault) | | | 2 MB | |/////////////////////|-. huge < |/////////////////////| > A(range) page | |/////////////////////|-' | | | | | | '-|---------------------| | | | | '---------------------' - Thread A is executing an madvise(..., MADV_DONTNEED) system call on the virtual address range "A(range)" shown in the picture. sys_madvise // Acquire the semaphore in shared mode. down_read(&current->mm->mmap_sem) ... madvise_vma switch (behavior) case MADV_DONTNEED: madvise_dontneed zap_page_range unmap_vmas unmap_page_range zap_pud_range zap_pmd_range // // Assume that this huge page has never been accessed. // I.e. content of the PMD entry is zero (not mapped). // if (pmd_trans_huge(*pmd)) { // We don't get here due to the above assumption. } // // Assume that Thread B incurred a page fault and .---------> // sneaks in here as shown below. | // | if (pmd_none_or_clear_bad(pmd)) | { | if (unlikely(pmd_bad(*pmd))) | pmd_clear_bad | { | pmd_ERROR | // Log "bad pmd ..." message here. | pmd_clear | // Clear the page's PMD entry. | // Thread B incremented the map count | // in page_add_new_anon_rmap(), but | // now the page is no longer mapped | // by a PMD entry (-> inconsistency). | } | } | v - Thread B is handling a page fault on virtual address "B(fault)" shown in the picture. ... do_page_fault __do_page_fault // Acquire the semaphore in shared mode. down_read_trylock(&mm->mmap_sem) ... handle_mm_fault if (pmd_none(*pmd) && transparent_hugepage_enabled(vma)) // We get here due to the above assumption (PMD entry is zero). do_huge_pmd_anonymous_page alloc_hugepage_vma // Allocate a new transparent huge page here. ... __do_huge_pmd_anonymous_page ... spin_lock(&mm->page_table_lock) ... page_add_new_anon_rmap // Here we increment the page's map count (starts at -1). atomic_set(&page->_mapcount, 0) set_pmd_at // Here we set the page's PMD entry which will be cleared // when Thread A calls pmd_clear_bad(). ... spin_unlock(&mm->page_table_lock) The mmap_sem does not prevent the race because both threads are acquiring it in shared mode (down_read). Thread B holds the page_table_lock while the page's map count and PMD table entry are updated. However, Thread A does not synchronize on that lock. ====== end quote ======= [akpm@linux-foundation.org: checkpatch fixes] Reported-by: Ulrich Obergfell <uobergfe@redhat.com> Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Hugh Dickins <hughd@google.com> Cc: Dave Jones <davej@redhat.com> Acked-by: Larry Woodman <lwoodman@redhat.com> Acked-by: Rik van Riel <riel@redhat.com> Cc: Mark Salter <msalter@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * x86/ioapic: Add register level checks to detect bogus io-apic entriesSuresh Siddha2012-04-021-8/+32
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 73d63d038ee9f769f5e5b46792d227fe20e442c5 upstream. With the recent changes to clear_IO_APIC_pin() which tries to clear remoteIRR bit explicitly, some of the users started to see "Unable to reset IRR for apic .." messages. Close look shows that these are related to bogus IO-APIC entries which return's all 1's for their io-apic registers. And the above mentioned error messages are benign. But kernel should have ignored such io-apic's in the first place. Check if register 0, 1, 2 of the listed io-apic are all 1's and ignore such io-apic. Reported-by: Álvaro Castillo <midgoon@gmail.com> Tested-by: Jon Dufresne <jon@jondufresne.org> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Cc: yinghai@kernel.org Cc: kernel-team@fedoraproject.org Cc: Josh Boyer <jwboyer@redhat.com> Link: http://lkml.kernel.org/r/1331577393.31585.94.camel@sbsiddha-desk.sc.intel.com [ Performed minor cleanup of affected code. ] Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * x86/amd: Fix L1i and L2 cache sharing information for AMD family 15h processorsAndreas Herrmann2012-02-291-8/+36
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 32c3233885eb10ac9cb9410f2f8cd64b8df2b2a1 upstream. For L1 instruction cache and L2 cache the shared CPU information is wrong. On current AMD family 15h CPUs those caches are shared between both cores of a compute unit. This fixes https://bugzilla.kernel.org/show_bug.cgi?id=42607 Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com> Cc: Petkov Borislav <Borislav.Petkov@amd.com> Cc: Dave Jones <davej@redhat.com> Link: http://lkml.kernel.org/r/20120208195229.GA17523@alberich.amd.com Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * i387: re-introduce FPU state preloading at context switch timeLinus Torvalds2012-02-293-25/+40
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 34ddc81a230b15c0e345b6b253049db731499f7e upstream. 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 b3b0870ef3ff ("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: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * i387: move TS_USEDFPU flag from thread_info to task_structLinus Torvalds2012-02-292-7/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit f94edacf998516ac9d849f7bc6949a703977a7f3 upstream. 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: Raphael Prevost <raphael@buro.asia> Acked-and-tested-by: Suresh Siddha <suresh.b.siddha@intel.com> Tested-by: Peter Anvin <hpa@zytor.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * i387: move AMD K7/K8 fpu fxsave/fxrstor workaround from save to restoreLinus Torvalds2012-02-292-3/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 4903062b5485f0e2c286a23b44c9b59d9b017d53 upstream. 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: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * i387: do not preload FPU state at task switch timeLinus Torvalds2012-02-293-67/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit b3b0870ef3ffed72b92415423da864f440f57ad6 upstream. 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: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * i387: don't ever touch TS_USEDFPU directly, use helper functionsLinus Torvalds2012-02-292-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 6d59d7a9f5b723a7ac1925c136e93ec83c0c3043 upstream. 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: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * i387: fix x86-64 preemption-unsafe user stack save/restoreLinus Torvalds2012-02-292-8/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 15d8791cae75dca27bfda8ecfe87dca9379d6bb0 upstream. Commit 5b1cbac37798 ("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: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * i387: make irq_fpu_usable() tests more robustLinus Torvalds2012-02-291-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 5b1cbac37798805c1fee18c8cebe5c0a13975b17 upstream. 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: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * i387: math_state_restore() isn't called from asmLinus Torvalds2012-02-291-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | commit be98c2cdb15ba26148cd2bd58a857d4f7759ed38 upstream. 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: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | Merge latest changes from google kernel/common.gitRoman Shaposhnikov2012-06-1312-109/+196
| | | | | | | | | | | | | | Kernel version updated to 3.0.31 Change-Id: Ifbd7150801f3beeec9cbaa566f249d8019ef9348 Signed-off-by: Roman Shaposhnikov <x0166637@ti.com>
* | sched: Cleanup cpu_active madnessPeter Zijlstra2012-05-161-13/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Stepan found: CPU0 CPUn _cpu_up() __cpu_up() boostrap() notify_cpu_starting() set_cpu_online() while (!cpu_active()) cpu_relax() <PREEMPT-out> smp_call_function(.wait=1) /* we find cpu_online() is true */ arch_send_call_function_ipi_mask() /* wait-forever-more */ <PREEMPT-in> local_irq_enable() cpu_notify(CPU_ONLINE) sched_cpu_active() set_cpu_active() Now the purpose of cpu_active is mostly with bringing down a cpu, where we mark it !active to avoid the load-balancer from moving tasks to it while we tear down the cpu. This is required because we only update the sched_domain tree after we brought the cpu-down. And this is needed so that some tasks can still run while we bring it down, we just don't want new tasks to appear. On cpu-up however the sched_domain tree doesn't yet include the new cpu, so its invisible to the load-balancer, regardless of the active state. So instead of setting the active state after we boot the new cpu (and consequently having to wait for it before enabling interrupts) set the cpu active before we set it online and avoid the whole mess. Change-Id: Ibad68784d481672eed23b0e8ad1d5fefc8755bd7 Reported-by: Stepan Moskovchenko <stepanm@codeaurora.org> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1323965362.18942.71.camel@twins Signed-off-by: Ingo Molnar <mingo@elte.hu> [taras@ti.com: backported from v3.4-rc1] Signed-off-by: Taras Kondratiuk <taras@ti.com>
* | Merge branch 'linux-3.0.19' into p-android-omap-3.0Dan Murphy2012-02-061-2/+22
|\ \ | |/ | | | | Signed-off-by: Dan Murphy <dmurphy@ti.com>
| * x86/microcode_amd: Add support for CPU family specific container filesAndreas Herrmann2012-02-031-2/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 5b68edc91cdc972c46f76f85eded7ffddc3ff5c2 upstream. 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: Andreas 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: Ingo Molnar <mingo@elte.hu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | Merge branch 'linux-3.0.18' into p-android-omap-3.0Dan Murphy2012-02-0210-28/+95
|\ \ | |/ | | | | | | | | | | | | | | | | | | Conflicts: arch/arm/mach-omap2/smartreflex.c drivers/i2c/busses/i2c-omap.c drivers/usb/host/ehci.h drivers/usb/musb/musb_core.c fs/proc/base.c Signed-off-by: Dan Murphy <dmurphy@ti.com>
| * x86, UV: Update Boot messages for SGI UV2 platformJack Steiner2012-01-251-1/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit da517a08ac5913cd80ce3507cddd00f2a091b13c upstream. 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: Jack Steiner <steiner@sgi.com> Link: http://lkml.kernel.org/r/20120106191900.GA19772@sgi.com Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| * x86/PCI: amd: factor out MMCONFIG discoveryBjorn Helgaas2012-01-251-0/+31
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 24d25dbfa63c376323096660bfa9ad45a08870ce upstream. 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> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| * x86, hpet: Immediately disable HPET timer 1 if rtc irq is maskedMark Langsdorf2011-12-211-7/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 2ded6e6a94c98ea453a156748cb7fabaf39a76b9 upstream. When HPET is operating in RTC mode, the TN_ENABLE bit on timer1 controls whether the HPET or the RTC delivers interrupts to irq8. When the system goes into suspend, the RTC driver sends a signal to the HPET driver so that the HPET releases control of irq8, allowing the RTC to wake the system from suspend. The switchover is accomplished by a write to the HPET configuration registers which currently only occurs while servicing the HPET interrupt. On some systems, I have seen the system suspend before an HPET interrupt occurs, preventing the write to the HPET configuration register and leaving the HPET in control of the irq8. As the HPET is not active during suspend, it does not generate a wake signal and RTC alarms do not work. This patch forces the HPET driver to immediately transfer control of the irq8 channel to the RTC instead of waiting until the next interrupt event. Signed-off-by: Mark Langsdorf <mark.langsdorf@amd.com> Link: http://lkml.kernel.org/r/20111118153306.GB16319@alberich.amd.com Tested-by: Andreas Herrmann <andreas.herrmann3@amd.com> Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| * perf/x86: Fix PEBS instruction unwindPeter Zijlstra2011-12-091-1/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 57d1c0c03c6b48b2b96870d831b9ce6b917f53ac upstream. Masami spotted that we always try to decode the instruction stream as 64bit instructions when running a 64bit kernel, this doesn't work for ia32-compat proglets. Use TIF_IA32 to detect if we need to use the 32bit instruction decoder. Reported-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| * x86: Fix "Acer Aspire 1" reboot hangPeter Chubb2011-12-091-2/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 1ef03890969932e9359b9a4c658f7f87771910ac upstream. Looks like on some Acer Aspire 1s with older bioses, reboot via bios fails. It works on my machine, (with BIOS version 0.3310) but not on some others (BIOS version 0.3309). There's a log of problems at: https://bbs.archlinux.org/viewtopic.php?id=124136 This patch adds a different callback to the reboot quirk table, to allow rebooting via keybaord controller. Reported-by: Uroš Vampl <mobile.leecher@gmail.com> Tested-by: Vasily Khoruzhick <anarsoul@gmail.com> Signed-off-by: Peter Chubb <peter.chubb@nicta.com.au> Cc: Don Zickus <dzickus@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1323093233-9481-1-git-send-email-anarsoul@gmail.com Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| * x86/mpparse: Account for bus types other than ISA and PCIBjorn Helgaas2011-12-091-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 9e6866686bdf2dcf3aeb0838076237ede532dcc8 upstream. In commit f8924e770e04 ("x86: unify mp_bus_info"), the 32-bit and 64-bit versions of MP_bus_info were rearranged to match each other better. Unfortunately it introduced a regression: prior to that change we used to always set the mp_bus_not_pci bit, then clear it if we found a PCI bus. After it, we set mp_bus_not_pci for ISA buses, clear it for PCI buses, and leave it alone otherwise. In the cases of ISA and PCI, there's not much difference. But ISA is not the only non-PCI bus, so it's better to always set mp_bus_not_pci and clear it only for PCI. Without this change, Dan's Dell PowerEdge 4200 panics on boot with a log indicating interrupt routing trouble unless the "noapic" option is supplied. With this change, the machine boots reliably without "noapic". Fixes http://bugs.debian.org/586494 Reported-bisected-and-tested-by: Dan McGrath <troubledaemon@gmail.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Cc: Dan McGrath <troubledaemon@gmail.com> Cc: Alexey Starikovskiy <aystarik@gmail.com> [jrnieder@gmail.com: clarified commit message] Signed-off-by: Jonathan Nieder <jrnieder@gmail.com> Link: http://lkml.kernel.org/r/20111122215000.GA9151@elie.hsd1.il.comcast.net Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| * iommu/amd: Fix wrong shift directionJoerg Roedel2011-11-111-1/+1
| | | | | | | | | | | | | | | | | | | | | | commit fcd0861db1cf4e6ed99f60a815b7b72c2ed36ea4 upstream. The shift direction was wrong because the function takes a page number and i is the address is the loop. Signed-off-by: Joerg Roedel <joerg.roedel@amd.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| * apic, i386/bigsmp: Fix false warnings regarding logical APIC ID mismatchesJan Beulich2011-11-112-12/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 838312be46f3abfbdc175f81c3e54a857994476d upstream. These warnings (generally one per CPU) are a result of initializing x86_cpu_to_logical_apicid while apic_default is still in use, but the check in setup_local_APIC() being done when apic_bigsmp was already used as an override in default_setup_apic_routing(): Overriding APIC driver with bigsmp Enabling APIC mode: Physflat. Using 5 I/O APICs ------------[ cut here ]------------ WARNING: at .../arch/x86/kernel/apic/apic.c:1239 ... CPU 1 irqstacks, hard=f1c9a000 soft=f1c9c000 Booting Node 0, Processors #1 smpboot cpu 1: start_ip = 9e000 Initializing CPU#1 ------------[ cut here ]------------ WARNING: at .../arch/x86/kernel/apic/apic.c:1239 setup_local_APIC+0x137/0x46b() Hardware name: ... CPU1 logical APIC ID: 2 != 8 ... Fix this (for the time being, i.e. until x86_32_early_logical_apicid() will get removed again, as Tejun says ought to be possible) by overriding the previously stored values at the point where the APIC driver gets overridden. v2: Move this and the pre-existing override logic into arch/x86/kernel/apic/bigsmp_32.c. Signed-off-by: Jan Beulich <jbeulich@suse.com> Acked-by: Tejun Heo <tj@kernel.org> Link: http://lkml.kernel.org/r/4E835D16020000780005844C@nat28.tlf.novell.com Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| * x86: Fix compilation bug in kprobes' twobyte_is_boostableJosh Stone2011-11-111-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 315eb8a2a1b7f335d40ceeeb11b9e067475eb881 upstream. When compiling an i386_defconfig kernel with gcc-4.6.1-9.fc15.i686, I noticed a warning about the asm operand for test_bit in kprobes' can_boost. I discovered that this caused only the first long of twobyte_is_boostable[] to be output. Jakub filed and fixed gcc PR50571 to correct the warning and this output issue. But to solve it for less current gcc, we can make kprobes' twobyte_is_boostable[] non-const, and it won't be optimized out. Before: CC arch/x86/kernel/kprobes.o In file included from include/linux/bitops.h:22:0, from include/linux/kernel.h:17, from [...]/arch/x86/include/asm/percpu.h:44, from [...]/arch/x86/include/asm/current.h:5, from [...]/arch/x86/include/asm/processor.h:15, from [...]/arch/x86/include/asm/atomic.h:6, from include/linux/atomic.h:4, from include/linux/mutex.h:18, from include/linux/notifier.h:13, from include/linux/kprobes.h:34, from arch/x86/kernel/kprobes.c:43: [...]/arch/x86/include/asm/bitops.h: In function ‘can_boost.part.1’: [...]/arch/x86/include/asm/bitops.h:319:2: warning: use of memory input without lvalue in asm operand 1 is deprecated [enabled by default] $ objdump -rd arch/x86/kernel/kprobes.o | grep -A1 -w bt 551: 0f a3 05 00 00 00 00 bt %eax,0x0 554: R_386_32 .rodata.cst4 $ objdump -s -j .rodata.cst4 -j .data arch/x86/kernel/kprobes.o arch/x86/kernel/kprobes.o: file format elf32-i386 Contents of section .data: 0000 48000000 00000000 00000000 00000000 H............... Contents of section .rodata.cst4: 0000 4c030000 L... Only a single long of twobyte_is_boostable[] is in the object file. After, without the const on twobyte_is_boostable: $ objdump -rd arch/x86/kernel/kprobes.o | grep -A1 -w bt 551: 0f a3 05 20 00 00 00 bt %eax,0x20 554: R_386_32 .data $ objdump -s -j .rodata.cst4 -j .data arch/x86/kernel/kprobes.o arch/x86/kernel/kprobes.o: file format elf32-i386 Contents of section .data: 0000 48000000 00000000 00000000 00000000 H............... 0010 00000000 00000000 00000000 00000000 ................ 0020 4c030000 0f000200 ffff0000 ffcff0c0 L............... 0030 0000ffff 3bbbfff8 03ff2ebb 26bb2e77 ....;.......&..w Now all 32 bytes are output into .data instead. Signed-off-by: Josh Stone <jistone@redhat.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Jakub Jelinek <jakub@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| * x86: uv2: Workaround for UV2 Hub bug (system global address format)Jack Steiner2011-11-111-2/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 6a469e4665bc158599de55d64388861d0a9f10f4 upstream. This is a workaround for a UV2 hub bug that affects the format of system global addresses. The GRU API for UV2 was inadvertently broken by a hardware change. The format of the physical address used for TLB dropins and for addresses used with instructions running in unmapped mode has changed. This change was not documented and became apparent only when diags failed running on system simulators. For UV1, TLB and GRU instruction physical addresses are identical to socket physical addresses (although high NASID bits must be OR'ed into the address). For UV2, socket physical addresses need to be converted. The NODE portion of the physical address needs to be shifted so that the low bit is in bit 39 or bit 40, depending on an MMR value. It is not yet clear if this bug will be fixed in a silicon respin. If it is fixed, the hub revision will be incremented & the workaround disabled. Signed-off-by: Jack Steiner <steiner@sgi.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* | Merge branch 'linux-omap-3.0' into android-omap-3.0Colin Cross2011-10-276-14/+42
|\ \ | |/
| * perf, x86: Add model 45 SandyBridge supportYouquan Song2011-10-031-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit a34668f6beb4ab01e07683276d6a24bab6c175e0 upstream. Add support to Romely-EP SandyBridge. Signed-off-by: Youquan Song <youquan.song@intel.com> Signed-off-by: Anhua Xu <anhua.xu@intel.com> Signed-off-by: Lin Ming <ming.m.lin@intel.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1312264895-2010-1-git-send-email-youquan.song@intel.com Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| * iommu/amd: Make sure iommu->need_sync contains correct valueJoerg Roedel2011-10-031-3/+10
| | | | | | | | | | | | | | | | | | | | | | | | commit f1ca1512e765337a7c09eb875eedef8ea4e07654 upstream. The value is only set to true but never set back to false, which causes to many completion-wait commands to be sent to hardware. Fix it with this patch. Signed-off-by: Joerg Roedel <joerg.roedel@amd.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| * iommu/amd: Don't take domain->lock recursivlyJoerg Roedel2011-10-031-5/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | commit e33acde91140f1809952d1c135c36feb66a51887 upstream. The domain_flush_devices() function takes the domain->lock. But this function is only called from update_domain() which itself is already called unter the domain->lock. This causes a deadlock situation when the dma-address-space of a domain grows larger than 1GB. Signed-off-by: Joerg Roedel <joerg.roedel@amd.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| * x86, perf: Check that current->mm is alive before getting user callchainAndrey Vagin2011-10-031-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 20afc60f892d285fde179ead4b24e6a7938c2f1b upstream. An event may occur when an mm is already released. I added an event in dequeue_entity() and caught a panic with the following backtrace: [ 434.421110] BUG: unable to handle kernel NULL pointer dereference at 0000000000000050 [ 434.421258] IP: [<ffffffff810464ac>] __get_user_pages_fast+0x9c/0x120 ... [ 434.421258] Call Trace: [ 434.421258] [<ffffffff8101ae81>] copy_from_user_nmi+0x51/0xf0 [ 434.421258] [<ffffffff8109a0d5>] ? sched_clock_local+0x25/0x90 [ 434.421258] [<ffffffff8101b048>] perf_callchain_user+0x128/0x170 [ 434.421258] [<ffffffff811154cd>] ? __perf_event_header__init_id+0xed/0x100 [ 434.421258] [<ffffffff81116690>] perf_prepare_sample+0x200/0x280 [ 434.421258] [<ffffffff81118da8>] __perf_event_overflow+0x1b8/0x290 [ 434.421258] [<ffffffff81065240>] ? tg_shares_up+0x0/0x670 [ 434.421258] [<ffffffff8104fe1a>] ? walk_tg_tree+0x6a/0xb0 [ 434.421258] [<ffffffff81118f44>] perf_swevent_overflow+0xc4/0xf0 [ 434.421258] [<ffffffff81119150>] do_perf_sw_event+0x1e0/0x250 [ 434.421258] [<ffffffff81119204>] perf_tp_event+0x44/0x70 [ 434.421258] [<ffffffff8105701f>] ftrace_profile_sched_block+0xdf/0x110 [ 434.421258] [<ffffffff8106121d>] dequeue_entity+0x2ad/0x2d0 [ 434.421258] [<ffffffff810614ec>] dequeue_task_fair+0x1c/0x60 [ 434.421258] [<ffffffff8105818a>] dequeue_task+0x9a/0xb0 [ 434.421258] [<ffffffff810581e2>] deactivate_task+0x42/0xe0 [ 434.421258] [<ffffffff814bc019>] thread_return+0x191/0x808 [ 434.421258] [<ffffffff81098a44>] ? switch_task_namespaces+0x24/0x60 [ 434.421258] [<ffffffff8106f4c4>] do_exit+0x464/0x910 [ 434.421258] [<ffffffff8106f9c8>] do_group_exit+0x58/0xd0 [ 434.421258] [<ffffffff8106fa57>] sys_exit_group+0x17/0x20 [ 434.421258] [<ffffffff8100b202>] system_call_fastpath+0x16/0x1b Signed-off-by: Andrey Vagin <avagin@openvz.org> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1314693156-24131-1-git-send-email-avagin@openvz.org Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| * x86, UV: Remove UV delay in starting slave cpusJack Steiner2011-08-291-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 05e33fc20ea5e493a2a1e7f1d04f43cdf89f83ed upstream. Delete the 10 msec delay between the INIT and SIPI when starting slave cpus. I can find no requirement for this delay. BIOS also has similar code sequences without the delay. Removing the delay reduces boot time by 40 sec. Every bit helps. Signed-off-by: Jack Steiner <steiner@sgi.com> Link: http://lkml.kernel.org/r/20110805140900.GA6774@sgi.com Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| * x86, mtrr: lock stop machine during MTRR rendezvous sequenceSuresh Siddha2011-08-291-0/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 6d3321e8e2b3bf6a5892e2ef673c7bf536e3f904 upstream. MTRR rendezvous sequence using stop_one_cpu_nowait() can potentially happen in parallel with another system wide rendezvous using stop_machine(). This can lead to deadlock (The order in which works are queued can be different on different cpu's. Some cpu's will be running the first rendezvous handler and others will be running the second rendezvous handler. Each set waiting for the other set to join for the system wide rendezvous, leading to a deadlock). MTRR rendezvous sequence is not implemented using stop_machine() as this gets called both from the process context aswell as the cpu online paths (where the cpu has not come online and the interrupts are disabled etc). stop_machine() works with only online cpus. For now, take the stop_machine mutex in the MTRR rendezvous sequence that gets called from an online cpu (here we are in the process context and can potentially sleep while taking the mutex). And the MTRR rendezvous that gets triggered during cpu online doesn't need to take this stop_machine lock (as the stop_machine() already ensures that there is no cpu hotplug going on in parallel by doing get_online_cpus()) TBD: Pursue a cleaner solution of extending the stop_machine() infrastructure to handle the case where the calling cpu is still not online and use this for MTRR rendezvous sequence. fixes: https://bugzilla.novell.com/show_bug.cgi?id=672008 Reported-by: Vadim Kotelnikov <vadimuzzz@inbox.ru> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Link: http://lkml.kernel.org/r/20110623182056.807230326@sbsiddha-MOBL3.sc.intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| * x86, intel, power: Correct the MSR_IA32_ENERGY_PERF_BIAS messageLen Brown2011-08-291-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 17edf2d79f1ea6dfdb4c444801d928953b9f98d6 upstream. Fix the printk_once() so that it actually prints (didn't print before due to a stray comma.) [ hpa: changed to an incremental patch and adjusted the description accordingly. ] Signed-off-by: Len Brown <len.brown@intel.com> Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1107151732480.18606@x980 Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* | Merge commit 'v3.0.1' into android-3.0Colin Cross2011-08-103-0/+22
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| * kexec, x86: Fix incorrect jump back address if not preserving contextHuang Ying2011-08-042-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 050438ed5a05b25cdf287f5691e56a58c2606997 upstream. In kexec jump support, jump back address passed to the kexeced kernel via function calling ABI, that is, the function call return address is the jump back entry. Furthermore, jump back entry == 0 should be used to signal that the jump back or preserve context is not enabled in the original kernel. But in the current implementation the stack position used for function call return address is not cleared context preservation is disabled. The patch fixes this bug. Reported-and-tested-by: Yin Kangkai <kangkai.yin@intel.com> Signed-off-by: Huang Ying <ying.huang@intel.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Vivek Goyal <vgoyal@redhat.com> Link: http://lkml.kernel.org/r/1310607277-25029-1-git-send-email-ying.huang@intel.com Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| * x86, intel, power: Initialize MSR_IA32_ENERGY_PERF_BIASLen Brown2011-08-041-0/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit abe48b108247e9b90b4c6739662a2e5c765ed114 upstream. Since 2.6.36 (23016bf0d25), Linux prints the existence of "epb" in /proc/cpuinfo, Since 2.6.38 (d5532ee7b40), the x86_energy_perf_policy(8) utility has been available in-tree to update MSR_IA32_ENERGY_PERF_BIAS. However, the typical BIOS fails to initialize the MSR, presumably because this is handled by high-volume shrink-wrap operating systems... Linux distros, on the other hand, do not yet invoke x86_energy_perf_policy(8). As a result, WSM-EP, SNB, and later hardware from Intel will run in its default hardware power-on state (performance), which assumes that users care for performance at all costs and not for energy efficiency. While that is fine for performance benchmarks, the hardware's intended default operating point is "normal" mode... Initialize the MSR to the "normal" by default during kernel boot. x86_energy_perf_policy(8) is available to change the default after boot, should the user have a different preference. Signed-off-by: Len Brown <len.brown@intel.com> Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1107140051020.18606@x980 Acked-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* | Merge commit 'v3.0' into android-3.0Colin Cross2011-08-101-0/+24
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| * x86: Make Dell Latitude E6420 use reboot=pciH. Peter Anvin2011-07-211-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Yet another variant of the Dell Latitude series which requires reboot=pci. From the E5420 bug report by Daniel J Blueman: > The E6420 is affected also (same platform, different casing and > features), which provides an external confirmation of the issue; I can > submit a patch for that later or include it if you prefer: > http://linux.koolsolutions.com/2009/08/04/howto-fix-linux-hangfreeze-during-reboots-and-restarts/ Reported-by: Daniel J Blueman <daniel.blueman@gmail.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Cc: <stable@kernel.org>
| * x86: Make Dell Latitude E5420 use reboot=pciDaniel J Blueman2011-07-211-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Rebooting on the Dell E5420 often hangs with the keyboard or ACPI methods, but is reliable via the PCI method. [ hpa: this was deferred because we believed for a long time that the recent reshuffling of the boot priorities in commit 660e34cebf0a11d54f2d5dd8838607452355f321 fixed this platform. Unfortunately that turned out to be incorrect. ] Signed-off-by: Daniel J Blueman <daniel.blueman@gmail.com> Link: http://lkml.kernel.org/r/1305248699-2347-1-git-send-email-daniel.blueman@gmail.com Signed-off-by: H. Peter Anvin <hpa@zytor.com> Cc: <stable@kernel.org>
| * x86. reboot: Make Dell Latitude E6320 use reboot=pciMaxime Ripard2011-07-121-0/+8
| | | | | | | | | | | | | | | | | | | | The Dell Latitude E6320 doesn't reboot unless reboot=pci is set. Force it thanks to DMI. Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com> Link: http://lkml.kernel.org/r/1309269451-4966-1-git-send-email-maxime.ripard@free-electrons.com Cc: Matthew Garrett <mjg@redhat.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* | Move x86_64 idle notifiers to genericTodd Poynor2011-07-151-16/+2
|/ | | | | | | | | Move the x86_64 idle notifiers originally by Andi Kleen and Venkatesh Pallipadi to generic. Change-Id: Idf29cda15be151f494ff245933c12462643388d5 Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org> Signed-off-by: Todd Poynor <toddpoynor@google.com>
* x86, suspend: Restore MISC_ENABLE MSR in realmode wakeupKees Cook2011-07-063-0/+26
| | | | | | | | | | | | | | | | | | | | | | | | | | Some BIOSes will reset the Intel MISC_ENABLE MSR (specifically the XD_DISABLE bit) when resuming from S3, which can interact poorly with ebba638ae723d8a8fc2f7abce5ec18b688b791d7. In 32bit PAE mode, this can lead to a fault when EFER is restored by the kernel wakeup routines, due to it setting the NX bit for a CPU that (thanks to the BIOS reset) now incorrectly thinks it lacks the NX feature. (64bit is not affected because it uses a common CPU bring-up that specifically handles the XD_DISABLE bit.) The need for MISC_ENABLE being restored so early is specific to the S3 resume path. Normally, MISC_ENABLE is saved in save_processor_state(), but this happens after the resume header is created, so just reproduce the logic here. (acpi_suspend_lowlevel() creates the header, calls do_suspend_lowlevel, which calls save_processor_state(), so the saved processor context isn't available during resume header creation.) [ hpa: Consider for stable if OK in mainline ] Signed-off-by: Kees Cook <kees.cook@canonical.com> Link: http://lkml.kernel.org/r/20110707011034.GA8523@outflux.net Signed-off-by: H. Peter Anvin <hpa@zytor.com> Cc: Rafael J. Wysocki <rjw@sisk.pl> Cc: <stable@kernel.org> 2.6.38+
* x86, reboot: Acer Aspire One A110 reboot quirkPeter Chubb2011-07-051-0/+8
| | | | | | | | | | | | | | | Since git commit 660e34cebf0a11d54f2d5dd8838607452355f321 x86: reorder reboot method preferences, my Acer Aspire One hangs on reboot. It appears that its ACPI method for rebooting is broken. The attached patch adds a quirk so that the machine will reboot via the BIOS. [ hpa: verified that the ACPI control on this machine is just plain broken. ] Signed-off-by: Peter Chubb <peter.chubb@nicta.com.au> Link: http://lkml.kernel.org/r/w439iki5vl.wl%25peter@chubb.wattle.id.au Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* x86 idle: APM requires pm_idle/default_idle unconditionally when a moduleAndy Whitcroft2011-06-141-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | [ Also from Ben Hutchings <ben@decadent.org.uk> and Vitaliy Ivanov <vitalivanov@gmail.com> ] Commit 06ae40ce073d ("x86 idle: EXPORT_SYMBOL(default_idle, pm_idle) only when APM demands it") removed the export for pm_idle/default_idle unless the apm module was modularised and CONFIG_APM_CPU_IDLE was set. But the apm module uses pm_idle/default_idle unconditionally, CONFIG_APM_CPU_IDLE only affects the bios idle threshold. Adjust the export accordingly. [ Used #ifdef instead of #if defined() as it's shorter, and what both Ben and Vitaliy used.. Andy, you're out-voted ;) - Linus ] Reported-by: Randy Dunlap <randy.dunlap@oracle.com> Acked-by: Jiri Kosina <jkosina@suse.cz> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Len Brown <len.brown@intel.com> Signed-off-by: Andy Whitcroft <apw@canonical.com> Signed-off-by: Vitaliy Ivanov <vitalivanov@gmail.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'drm-fixes' of ↵Linus Torvalds2011-06-141-4/+4
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6 * 'drm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6: drm: Compare only lower 32 bits of framebuffer map offsets drm/i915: Don't leak in i915_gem_shmem_pread_slow() drm/radeon/kms: do bounds checking for 3D_LOAD_VBPNTR and bump array limit drm/radeon/kms: fix mac g5 quirk x86/uv/x2apic: update for change in pci bridge handling. alpha, drm: Remove obsolete Alpha support in MGA DRM code alpha/drm: Cleanup Alpha support in DRM generic code savage: remove unnecessary if statement drm/radeon: fix GUI idle IH debug statements drm/radeon/kms: check modes against max pixel clock drm: fix fbs in DRM_IOCTL_MODE_GETRESOURCES ioctl
| * x86/uv/x2apic: update for change in pci bridge handling.Dave Airlie2011-06-141-4/+4
| | | | | | | | | | | | | | | | | | | | When I added 3448a19da479b6bd1e28e2a2be9fa16c6a6feb39 I forgot about the special uv handling code for this, so this patch fixes it up. Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org> Acked-by: Ingo Molnar Signed-off-by: Dave Airlie <airlied@redhat.com>
* | Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds2011-06-131-1/+2
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: ftrace: Revert 8ab2b7efd ftrace: Remove unnecessary disabling of irqs kprobes/trace: Fix kprobe selftest for gcc 4.6 ftrace: Fix possible undefined return code oprofile, dcookies: Fix possible circular locking dependency oprofile: Fix locking dependency in sync_start() oprofile: Free potentially owned tasks in case of errors oprofile, x86: Add comments to IBS LVT offset initialization
| * \ Merge branch 'urgent' of ↵Ingo Molnar2011-06-081-1/+2
| |\ \ | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rric/oprofile into perf/urgent
generated by cgit v1.1 at 2025-08-16 03:26:49 +0000