- 19 Oct, 2010 2 commits
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Jeremy Fitzhardinge authored
Take mm->page_table_lock while syncing the vmalloc region. This prevents a race with the Xen pagetable pin/unpin code, which expects that the page_table_lock is already held. If this race occurs, then Xen can see an inconsistent page type (a page can either be read/write or a pagetable page, and pin/unpin converts it between them), which will cause either the pin or the set_p[gm]d to fail; either will crash the kernel. vmalloc_sync_all() should be called rarely, so this extra use of page_table_lock should not interfere with its normal users. The mm pointer is stashed in the pgd page's index field, as that won't be otherwise used for pgds. Reported-by: Ian Campbell <ian.cambell@eu.citrix.com> Originally-by: Jan Beulich <jbeulich@novell.com> LKML-Reference: <4CB88A4C.1080305@goop.org> Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
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Jeremy Fitzhardinge authored
Whitespace cleanup only. Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
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- 07 Oct, 2010 1 commit
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Namhyung Kim authored
On 32-bit non-PAE system, cast to 'phys_addr_t' truncates value before subtraction. Subtracting before cast produce same result but remove following warnings from sparse: arch/x86/include/asm/pgtable_types.h:255:38: warning: cast truncates bits from constant value (100000000 becomes 0) arch/x86/include/asm/pgtable_types.h:270:38: warning: cast truncates bits from constant value (100000000 becomes 0) arch/x86/include/asm/pgtable.h:127:32: warning: cast truncates bits from constant value (100000000 becomes 0) arch/x86/include/asm/pgtable.h:132:32: warning: cast truncates bits from constant value (100000000 becomes 0) arch/x86/include/asm/pgtable.h:344:31: warning: cast truncates bits from constant value (100000000 becomes 0) 64-bit or PAE machines will not be affected by this change. Signed-off-by: Namhyung Kim <namhyung@gmail.com> LKML-Reference: <1285770588-14065-1-git-send-email-namhyung@gmail.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
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- 06 Oct, 2010 1 commit
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Jeremy Fitzhardinge authored
This is useful when converting static arrays into boot-time brk allocated objects. Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> LKML-Reference: <4C805EEA.1080205@goop.org> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
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- 17 Sep, 2010 1 commit
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Cliff Wickman authored
During the reading of /proc/vmcore the kernel is doing ioremap()/iounmap() repeatedly. And the buildup of un-flushed vm_area_struct's is causing a great deal of overhead. (rb_next() is chewing up most of that time). This solution is to provide function set_iounmap_nonlazy(). It causes a subsequent call to iounmap() to immediately purge the vma area (with try_purge_vmap_area_lazy()). With this patch we have seen the time for writing a 250MB compressed dump drop from 71 seconds to 44 seconds. Signed-off-by: Cliff Wickman <cpw@sgi.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: kexec@lists.infradead.org Cc: <stable@kernel.org> LKML-Reference: <E1OwHZ4-0005WK-Tw@eag09.americas.sgi.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
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- 09 Sep, 2010 1 commit
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Cliff Wickman authored
The copy of /proc/vmcore to a user buffer proceeds much faster if the kernel addresses memory as cached. With this patch we have seen an increase in transfer rate from less than 15MB/s to 80-460MB/s, depending on size of the transfer. This makes a big difference in time needed to save a system dump. Signed-off-by: Cliff Wickman <cpw@sgi.com> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Cc: kexec@lists.infradead.org Cc: <stable@kernel.org> # as far back as it would apply LKML-Reference: <E1OtMLz-0001yp-Ia@eag09.americas.sgi.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
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- 03 Sep, 2010 1 commit
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Wu Fengguang authored
This re-adds the lost chunk in commit 9b861528. Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Haicheng Li <haicheng.li@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> LKML-Reference: <20100903090407.GA19771@localhost> Signed-off-by: Ingo Molnar <mingo@elte.hu>
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- 30 Aug, 2010 1 commit
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Julia Lawall authored
The opcodes 0x2e and 0x3e are tested for in the first Group 2 line as well. The sematic match that finds this problem is as follows: (http://coccinelle.lip6.fr/) // <smpl> @expression@ expression E; @@ ( * E || ... || E | * E && ... && E ) // </smpl> Signed-off-by: Julia Lawall <julia@diku.dk> Reviewed-by: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Vegard Nossum <vegardno@ifi.uio.no> LKML-Reference: <1283010066-20935-5-git-send-email-julia@diku.dk> Signed-off-by: Ingo Molnar <mingo@elte.hu>
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- 26 Aug, 2010 3 commits
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Shaohua Li authored
pte_present() returns true even present bit isn't set but _PAGE_PROTNONE (global bit) bit is set. While with CONFIG_DEBUG_PAGEALLOC, free pages have global bit set but present bit clear. This patch makes we could catch free pages access with CONFIG_DEBUG_PAGEALLOC enabled. [ hpa: added a comment in the code as a warning to janitors ] Signed-off-by: Shaohua Li <shaohua.li@intel.com> LKML-Reference: <1280217988.32400.75.camel@sli10-desk.sh.intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
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Haicheng Li authored
When memory hotplug-adding happens for a large enough area that a new PGD entry is needed for the direct mapping, the PGDs of other processes would not get updated. This leads to some CPUs oopsing like below when they have to access the unmapped areas. [ 1139.243192] BUG: soft lockup - CPU#0 stuck for 61s! [bash:6534] [ 1139.243195] Modules linked in: ipv6 autofs4 rfcomm l2cap crc16 bluetooth rfkill binfmt_misc dm_mirror dm_region_hash dm_log dm_multipath dm_mod video output sbs sbshc fan battery ac parport_pc lp parport joydev usbhid processor thermal thermal_sys container button rtc_cmos rtc_core rtc_lib i2c_i801 i2c_core pcspkr uhci_hcd ohci_hcd ehci_hcd usbcore [ 1139.243229] irq event stamp: 8538759 [ 1139.243230] hardirqs last enabled at (8538759): [<ffffffff8100c3fc>] restore_args+0x0/0x30 [ 1139.243236] hardirqs last disabled at (8538757): [<ffffffff810422df>] __do_softirq+0x106/0x146 [ 1139.243240] softirqs last enabled at (8538758): [<ffffffff81042310>] __do_softirq+0x137/0x146 [ 1139.243245] softirqs last disabled at (8538743): [<ffffffff8100cb5c>] call_softirq+0x1c/0x34 [ 1139.243249] CPU 0: [ 1139.243250] Modules linked in: ipv6 autofs4 rfcomm l2cap crc16 bluetooth rfkill binfmt_misc dm_mirror dm_region_hash dm_log dm_multipath dm_mod video output sbs sbshc fan battery ac parport_pc lp parport joydev usbhid processor thermal thermal_sys container button rtc_cmos rtc_core rtc_lib i2c_i801 i2c_core pcspkr uhci_hcd ohci_hcd ehci_hcd usbcore [ 1139.243284] Pid: 6534, comm: bash Tainted: G M 2.6.32-haicheng-cpuhp #7 QSSC-S4R [ 1139.243287] RIP: 0010:[<ffffffff810ace35>] [<ffffffff810ace35>] alloc_arraycache+0x35/0x69 [ 1139.243292] RSP: 0018:ffff8802799f9d78 EFLAGS: 00010286 [ 1139.243295] RAX: ffff8884ffc00000 RBX: ffff8802799f9d98 RCX: 0000000000000000 [ 1139.243297] RDX: 0000000000190018 RSI: 0000000000000001 RDI: ffff8884ffc00010 [ 1139.243300] RBP: ffffffff8100c34e R08: 0000000000000002 R09: 0000000000000000 [ 1139.243303] R10: ffffffff8246dda0 R11: 000000d08246dda0 R12: ffff8802599bfff0 [ 1139.243305] R13: ffff88027904c040 R14: ffff8802799f8000 R15: 0000000000000001 [ 1139.243308] FS: 00007fe81bfe86e0(0000) GS:ffff88000d800000(0000) knlGS:0000000000000000 [ 1139.243311] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1139.243313] CR2: ffff8884ffc00000 CR3: 000000026cf2d000 CR4: 00000000000006f0 [ 1139.243316] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 1139.243318] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 [ 1139.243321] Call Trace: [ 1139.243324] [<ffffffff810ace29>] ? alloc_arraycache+0x29/0x69 [ 1139.243328] [<ffffffff8135004e>] ? cpuup_callback+0x1b0/0x32a [ 1139.243333] [<ffffffff8105385d>] ? notifier_call_chain+0x33/0x5b [ 1139.243337] [<ffffffff810538a4>] ? __raw_notifier_call_chain+0x9/0xb [ 1139.243340] [<ffffffff8134ecfc>] ? cpu_up+0xb3/0x152 [ 1139.243344] [<ffffffff813388ce>] ? store_online+0x4d/0x75 [ 1139.243348] [<ffffffff811e53f3>] ? sysdev_store+0x1b/0x1d [ 1139.243351] [<ffffffff8110589f>] ? sysfs_write_file+0xe5/0x121 [ 1139.243355] [<ffffffff810b539d>] ? vfs_write+0xae/0x14a [ 1139.243358] [<ffffffff810b587f>] ? sys_write+0x47/0x6f [ 1139.243362] [<ffffffff8100b9ab>] ? system_call_fastpath+0x16/0x1b This patch makes sure to always replicate new direct mapping PGD entries to the PGDs of all processes, as well as ensures corresponding vmemmap mapping gets synced. V1: initial code by Andi Kleen. V2: fix several issues found in testing. V3: as suggested by Wu Fengguang, reuse common code of vmalloc_sync_all(). [ hpa: changed pgd_change from int to bool ] Originally-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Haicheng Li <haicheng.li@linux.intel.com> LKML-Reference: <4C6E4FD8.6080100@linux.intel.com> Reviewed-by: Wu Fengguang <fengguang.wu@intel.com> Reviewed-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
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Haicheng Li authored
No behavior change. Move some of vmalloc_sync_all() code into a new function sync_global_pgds() that will be useful for memory hotplug. Signed-off-by: Haicheng Li <haicheng.li@linux.intel.com> LKML-Reference: <4C6E4ECD.1090607@linux.intel.com> Reviewed-by: Wu Fengguang <fengguang.wu@intel.com> Reviewed-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
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- 23 Aug, 2010 2 commits
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Shaohua Li authored
In x86, access and dirty bits are set automatically by CPU when CPU accesses memory. When we go into the code path of below flush_tlb_fix_spurious_fault(), we already set dirty bit for pte and don't need flush tlb. This might mean tlb entry in some CPUs hasn't dirty bit set, but this doesn't matter. When the CPUs do page write, they will automatically check the bit and no software involved. On the other hand, flush tlb in below position is harmful. Test creates CPU number of threads, each thread writes to a same but random address in same vma range and we measure the total time. Under a 4 socket system, original time is 1.96s, while with the patch, the time is 0.8s. Under a 2 socket system, there is 20% time cut too. perf shows a lot of time are taking to send ipi/handle ipi for tlb flush. Signed-off-by: Shaohua Li <shaohua.li@intel.com> LKML-Reference: <20100816011655.GA362@sli10-desk.sh.intel.com> Acked-by: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Andrea Archangeli <aarcange@redhat.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
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Linus Torvalds authored
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- 22 Aug, 2010 12 commits
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git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds authored
* 'kvm-updates/2.6.36' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: PIT: free irq source id in handling error path KVM: destroy workqueue on kvm_create_pit() failures KVM: fix poison overwritten caused by using wrong xstate size
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git://git.kernel.org/pub/scm/linux/kernel/git/anholt/drm-intelLinus Torvalds authored
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/anholt/drm-intel: (58 commits) drm/i915,intel_agp: Add support for Sandybridge D0 drm/i915: fix render pipe control notify on sandybridge agp/intel: set 40-bit dma mask on Sandybridge drm/i915: Remove the conflicting BUG_ON() drm/i915/suspend: s/IS_IRONLAKE/HAS_PCH_SPLIT/ drm/i915/suspend: Flush register writes before busy-waiting. i915: disable DAC on Ironlake also when doing CRT load detection. drm/i915: wait for actual vblank, not just 20ms drm/i915: make sure eDP PLL is enabled at the right time drm/i915: fix VGA plane disable for Ironlake+ drm/i915: eDP mode set sequence corrections drm/i915: add panel reset workaround drm/i915: Enable RC6 on Ironlake. drm/i915/sdvo: Only set is_lvds if we have a valid fixed mode. drm/i915: Set up a render context on Ironlake drm/i915 invalidate indirect state pointers at end of ring exec drm/i915: Wake-up wait_request() from elapsed hang-check (v2) drm/i915: Apply i830 errata for cursor alignment drm/i915: Only update i845/i865 CURBASE when disabled (v2) drm/i915: FBC is updated within set_base() so remove second call in mode_set() ...
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git://git.kernel.org/pub/scm/linux/kernel/git/penberg/slab-2.6Linus Torvalds authored
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/slab-2.6: slab: fix object alignment slub: add missing __percpu markup in mm/slub_def.h
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git://git.kernel.org/pub/scm/linux/kernel/git/ryusuke/nilfs2Linus Torvalds authored
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ryusuke/nilfs2: nilfs2: wait for discard to finish
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Zhenyu Wang authored
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com> Signed-off-by: Eric Anholt <eric@anholt.net>
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Zhenyu Wang authored
This one is missed in last pipe control fix for sandybridge, that really unmask interrupt bit for notify in render engine IMR. Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com> Signed-off-by: Eric Anholt <eric@anholt.net>
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Zhenyu Wang authored
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com> Signed-off-by: Eric Anholt <eric@anholt.net>
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Chris Wilson authored
We now attempt to free "active" objects following a GPU hang as either the GPU will be reset or the hang is permenant. In either case, the GPU writes will not be flushed to main memory and it should be safe to return that memory back to the system. The BUG_ON(active) is thus overkill and can erroneously fire after a EIO. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Eric Anholt <eric@anholt.net>
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Chris Wilson authored
For the shared paths on the next generation chipsets. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Eric Anholt <eric@anholt.net>
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Chris Wilson authored
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Eric Anholt <eric@anholt.net>
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Dave Airlie authored
Like on Sandybridge, disabling the DAC here when doing CRT load detect avoids forever hangs waiting on the hardware. test procedure on HP 2740p: boot with no VGA plugged in, start X, plug in VGA monitor (1280x1024) chvt 3 machine hangs waiting forever. Signed-off-by: Dave Airlie <airlied@redhat.com> Signed-off-by: Eric Anholt <eric@anholt.net>
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Jesse Barnes authored
Waiting for a hard coded 20ms isn't always enough to make sure a vblank period has actually occurred, so add code to make sure we really have passed through a vblank period (or that the pipe is off when disabling). This prevents problems with mode setting and link training, and seems to fix a bug like https://bugs.freedesktop.org/show_bug.cgi?id=29278, but on an HP 8440p instead. Hopefully also fixes https://bugs.freedesktop.org/show_bug.cgi?id=29141. Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org> Signed-off-by: Eric Anholt <eric@anholt.net>
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- 21 Aug, 2010 6 commits
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Arjan van de Ven authored
With the introduction of the new unified work queue thread pools, we lost one feature: It's no longer possible to know which worker is causing the CPU to wake out of idle. The result is that PowerTOP now reports a lot of "kworker/a:b" instead of more readable results. This patch adds a pair of tracepoints to the new workqueue code, similar in style to the timer/hrtimer tracepoints. With this pair of tracepoints, the next PowerTOP can correctly report which work item caused the wakeup (and how long it took): Interrupt (43) i915 time 3.51ms wakeups 141 Work ieee80211_iface_work time 0.81ms wakeups 29 Work do_dbs_timer time 0.55ms wakeups 24 Process Xorg time 21.36ms wakeups 4 Timer sched_rt_period_timer time 0.01ms wakeups 1 Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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git://git.infradead.org/mtd-2.6Linus Torvalds authored
* git://git.infradead.org/mtd-2.6: mtd: nand: Fix probe of Samsung NAND chips mtd: nand: Fix regression in BBM detection pxa3xx: fix ns2cycle equation
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Samuel Thibault authored
The "Configure" word tends to make user believe they have to say 'yes' to be able to choose the number of procs/nodes. "Enable" should be unambiguous enough. Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Linus Torvalds authored
Like the mlock() change previously, this makes the stack guard check code use vma->vm_prev to see what the mapping below the current stack is, rather than have to look it up with find_vma(). Also, accept an abutting stack segment, since that happens naturally if you split the stack with mlock or mprotect. Tested-by: Ian Campbell <ijc@hellion.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Linus Torvalds authored
If we've split the stack vma, only the lowest one has the guard page. Now that we have a doubly linked list of vma's, checking this is trivial. Tested-by: Ian Campbell <ijc@hellion.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Linus Torvalds authored
It's a really simple list, and several of the users want to go backwards in it to find the previous vma. So rather than have to look up the previous entry with 'find_vma_prev()' or something similar, just make it doubly linked instead. Tested-by: Ian Campbell <ijc@hellion.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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- 20 Aug, 2010 9 commits
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Tilman Sauerbeck authored
Apparently, the check for a 6-byte ID string introduced by commit 426c457a ("mtd: nand: extend NAND flash detection to new MLC chips") is NOT sufficient to determine whether or not a Samsung chip uses their new MLC detection scheme or the old, standard scheme. This adds a condition to check cell type. Signed-off-by: Tilman Sauerbeck <tilman@code-monkey.de> Signed-off-by: Brian Norris <norris@broadcom.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com> Cc: stable@kernel.org
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Linus Torvalds authored
Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, apic: Fix apic=debug boot crash x86, hotplug: Serialize CPU hotplug to avoid bringup concurrency issues x86-32: Fix dummy trampoline-related inline stubs x86-32: Separate 1:1 pagetables from swapper_pg_dir x86, cpu: Fix regression in AMD errata checking code
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Stephen Rothwell authored
This list moved to lists.ozlabs.org quite some time ago. Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Stephen Rothwell authored
All these lists moved to lists.ozlabs.org quite a while ago. Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Stefan Richter authored
Chapter 6 is right about mutex_trylock, but chapter 10 wasn't. This error was introduced during semaphore-to-mutex conversion of the Unreliable guide. :-) If user context which performs mutex_lock() or mutex_trylock() is preempted by interrupt context which performs mutex_trylock() on the same mutex instance, a deadlock occurs. This is because these functions do not disable local IRQs when they operate on mutex->wait_lock. Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Matthew Wilcox <matthew@wil.cx> Cc: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Andrew Morton authored
gcc-4.0.2: drivers/scsi/qla4xxx/ql4_os.c: In function 'qla4_8xxx_error_recovery': drivers/scsi/qla4xxx/ql4_glbl.h:135: sorry, unimplemented: inlining failed in call to 'qla4_8xxx_set_drv_active': function body not available drivers/scsi/qla4xxx/ql4_os.c:2377: sorry, unimplemented: called from here drivers/scsi/qla4xxx/ql4_glbl.h:135: sorry, unimplemented: inlining failed in call to 'qla4_8xxx_set_drv_active': function body not available drivers/scsi/qla4xxx/ql4_os.c:2393: sorry, unimplemented: called from here Cc: Ravi Anand <ravi.anand@qlogic.com> Cc: Vikas Chaudhary <vikas.chaudhary@qlogic.com> Cc: James Bottomley <James.Bottomley@HansenPartnership.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Miklos Szeredi authored
Fix uml compile error: include/linux/dma-mapping.h:145: error: redefinition of 'dma_get_cache_alignment' arch/um/include/asm/dma-mapping.h:99: note: previous definition of 'dma_get_cache_alignment' was here Introduced by commit 4565f017 ("dma-mapping: unify dma_get_cache_alignment implementations") Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Jeff Dike <jdike@addtoit.com> Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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KOSAKI Motohiro authored
dump_tasks() needs to hold the RCU read lock around its access of the target task's UID. To this end it should use task_uid() as it only needs that one thing from the creds. The fact that dump_tasks() holds tasklist_lock is insufficient to prevent the target process replacing its credentials on another CPU. Then, this patch change to call rcu_read_lock() explicitly. =================================================== [ INFO: suspicious rcu_dereference_check() usage. ] --------------------------------------------------- mm/oom_kill.c:410 invoked rcu_dereference_check() without protection! other info that might help us debug this: rcu_scheduler_active = 1, debug_locks = 1 4 locks held by kworker/1:2/651: #0: (events){+.+.+.}, at: [<ffffffff8106aae7>] process_one_work+0x137/0x4a0 #1: (moom_work){+.+...}, at: [<ffffffff8106aae7>] process_one_work+0x137/0x4a0 #2: (tasklist_lock){.+.+..}, at: [<ffffffff810fafd4>] out_of_memory+0x164/0x3f0 #3: (&(&p->alloc_lock)->rlock){+.+...}, at: [<ffffffff810fa48e>] find_lock_task_mm+0x2e/0x70 Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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KOSAKI Motohiro authored
Commit 0aad4b31 ("oom: fold __out_of_memory into out_of_memory") introduced a tasklist_lock leak. Then it caused following obvious danger warnings and panic. ================================================ [ BUG: lock held when returning to user space! ] ------------------------------------------------ rsyslogd/1422 is leaving the kernel with locks still held! 1 lock held by rsyslogd/1422: #0: (tasklist_lock){.+.+.+}, at: [<ffffffff810faf64>] out_of_memory+0x164/0x3f0 BUG: scheduling while atomic: rsyslogd/1422/0x00000002 INFO: lockdep is turned off. This patch fixes it. Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Reviewed-by: Minchan Kim <minchan.kim@gmail.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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