- 26 Mar, 2015 1 commit
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git://git.kernel.org/pub/scm/linux/kernel/git/s390/linuxLinus Torvalds authored
Pull s390 fixes from Martin Schwidefsky: "A couple of bug fixes for s390. The ftrace comile fix is quite large for a -rc6 release, but it would be nice to have it in 4.0" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: s390/smp: reenable smt after resume s390/mm: limit STACK_RND_MASK for compat tasks s390/ftrace: fix compile error if CONFIG_KPROBES is disabled s390/cpum_sf: add diagnostic sampling event only if it is authorized
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- 25 Mar, 2015 24 commits
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git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/metagLinus Torvalds authored
Pull arch/metag fix from James Hogan: "Another metag architecture fix for v4.0 This is another single fix, for an include dependency problem when using ioremap_wc() from asm/io.h without also including asm/pgtable.h" * tag 'metag-fixes-v4.0-2' of git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/metag: metag: Fix ioremap_wc/ioremap_cached build errors
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Linus Torvalds authored
Merge misc fixes from Andrew Morton: "15 fixes" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: mm: numa: mark huge PTEs young when clearing NUMA hinting faults mm: numa: slow PTE scan rate if migration failures occur mm: numa: preserve PTE write permissions across a NUMA hinting fault mm: numa: group related processes based on VMA flags instead of page table flags hfsplus: fix B-tree corruption after insertion at position 0 MAINTAINERS: add Jan as DMI/SMBIOS support maintainer fs/affs/file.c: unlock/release page on error mm/page_alloc.c: call kernel_map_pages in unset_migrateype_isolate mm/slub: fix lockups on PREEMPT && !SMP kernels mm/memory hotplug: postpone the reset of obsolete pgdat MAINTAINERS: correct rtc armada38x pattern entry mm/pagewalk.c: prevent positive return value of walk_page_test() from being passed to callers mm: fix anon_vma->degree underflow in anon_vma endless growing prevention drivers/rtc/rtc-mrst: fix suspend/resume aoe: update aoe maintainer information
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Mel Gorman authored
Base PTEs are marked young when the NUMA hinting information is cleared but the same does not happen for huge pages which this patch addresses. Note that migrated pages are not marked young as the base page migration code does not assume that migrated pages have been referenced. This could be addressed but beyond the scope of this series which is aimed at Dave Chinners shrink workload that is unlikely to be affected by this issue. Signed-off-by: Mel Gorman <mgorman@suse.de> Cc: Dave Chinner <david@fromorbit.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Aneesh Kumar <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Mel Gorman authored
Dave Chinner reported the following on https://lkml.org/lkml/2015/3/1/226 Across the board the 4.0-rc1 numbers are much slower, and the degradation is far worse when using the large memory footprint configs. Perf points straight at the cause - this is from 4.0-rc1 on the "-o bhash=101073" config: - 56.07% 56.07% [kernel] [k] default_send_IPI_mask_sequence_phys - default_send_IPI_mask_sequence_phys - 99.99% physflat_send_IPI_mask - 99.37% native_send_call_func_ipi smp_call_function_many - native_flush_tlb_others - 99.85% flush_tlb_page ptep_clear_flush try_to_unmap_one rmap_walk try_to_unmap migrate_pages migrate_misplaced_page - handle_mm_fault - 99.73% __do_page_fault trace_do_page_fault do_async_page_fault + async_page_fault 0.63% native_send_call_func_single_ipi generic_exec_single smp_call_function_single This is showing excessive migration activity even though excessive migrations are meant to get throttled. Normally, the scan rate is tuned on a per-task basis depending on the locality of faults. However, if migrations fail for any reason then the PTE scanner may scan faster if the faults continue to be remote. This means there is higher system CPU overhead and fault trapping at exactly the time we know that migrations cannot happen. This patch tracks when migration failures occur and slows the PTE scanner. Signed-off-by: Mel Gorman <mgorman@suse.de> Reported-by: Dave Chinner <david@fromorbit.com> Tested-by: Dave Chinner <david@fromorbit.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Aneesh Kumar <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Mel Gorman authored
Protecting a PTE to trap a NUMA hinting fault clears the writable bit and further faults are needed after trapping a NUMA hinting fault to set the writable bit again. This patch preserves the writable bit when trapping NUMA hinting faults. The impact is obvious from the number of minor faults trapped during the basis balancing benchmark and the system CPU usage; autonumabench 4.0.0-rc4 4.0.0-rc4 baseline preserve Time System-NUMA01 107.13 ( 0.00%) 103.13 ( 3.73%) Time System-NUMA01_THEADLOCAL 131.87 ( 0.00%) 83.30 ( 36.83%) Time System-NUMA02 8.95 ( 0.00%) 10.72 (-19.78%) Time System-NUMA02_SMT 4.57 ( 0.00%) 3.99 ( 12.69%) Time Elapsed-NUMA01 515.78 ( 0.00%) 517.26 ( -0.29%) Time Elapsed-NUMA01_THEADLOCAL 384.10 ( 0.00%) 384.31 ( -0.05%) Time Elapsed-NUMA02 48.86 ( 0.00%) 48.78 ( 0.16%) Time Elapsed-NUMA02_SMT 47.98 ( 0.00%) 48.12 ( -0.29%) 4.0.0-rc4 4.0.0-rc4 baseline preserve User 44383.95 43971.89 System 252.61 201.24 Elapsed 998.68 1000.94 Minor Faults 2597249 1981230 Major Faults 365 364 There is a similar drop in system CPU usage using Dave Chinner's xfsrepair workload 4.0.0-rc4 4.0.0-rc4 baseline preserve Amean real-xfsrepair 454.14 ( 0.00%) 442.36 ( 2.60%) Amean syst-xfsrepair 277.20 ( 0.00%) 204.68 ( 26.16%) The patch looks hacky but the alternatives looked worse. The tidest was to rewalk the page tables after a hinting fault but it was more complex than this approach and the performance was worse. It's not generally safe to just mark the page writable during the fault if it's a write fault as it may have been read-only for COW so that approach was discarded. Signed-off-by: Mel Gorman <mgorman@suse.de> Reported-by: Dave Chinner <david@fromorbit.com> Tested-by: Dave Chinner <david@fromorbit.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Aneesh Kumar <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Mel Gorman authored
These are three follow-on patches based on the xfsrepair workload Dave Chinner reported was problematic in 4.0-rc1 due to changes in page table management -- https://lkml.org/lkml/2015/3/1/226. Much of the problem was reduced by commit 53da3bc2 ("mm: fix up numa read-only thread grouping logic") and commit ba68bc01 ("mm: thp: Return the correct value for change_huge_pmd"). It was known that the performance in 3.19 was still better even if is far less safe. This series aims to restore the performance without compromising on safety. For the test of this mail, I'm comparing 3.19 against 4.0-rc4 and the three patches applied on top autonumabench 3.19.0 4.0.0-rc4 4.0.0-rc4 4.0.0-rc4 4.0.0-rc4 vanilla vanilla vmwrite-v5r8 preserve-v5r8 slowscan-v5r8 Time System-NUMA01 124.00 ( 0.00%) 161.86 (-30.53%) 107.13 ( 13.60%) 103.13 ( 16.83%) 145.01 (-16.94%) Time System-NUMA01_THEADLOCAL 115.54 ( 0.00%) 107.64 ( 6.84%) 131.87 (-14.13%) 83.30 ( 27.90%) 92.35 ( 20.07%) Time System-NUMA02 9.35 ( 0.00%) 10.44 (-11.66%) 8.95 ( 4.28%) 10.72 (-14.65%) 8.16 ( 12.73%) Time System-NUMA02_SMT 3.87 ( 0.00%) 4.63 (-19.64%) 4.57 (-18.09%) 3.99 ( -3.10%) 3.36 ( 13.18%) Time Elapsed-NUMA01 570.06 ( 0.00%) 567.82 ( 0.39%) 515.78 ( 9.52%) 517.26 ( 9.26%) 543.80 ( 4.61%) Time Elapsed-NUMA01_THEADLOCAL 393.69 ( 0.00%) 384.83 ( 2.25%) 384.10 ( 2.44%) 384.31 ( 2.38%) 380.73 ( 3.29%) Time Elapsed-NUMA02 49.09 ( 0.00%) 49.33 ( -0.49%) 48.86 ( 0.47%) 48.78 ( 0.63%) 50.94 ( -3.77%) Time Elapsed-NUMA02_SMT 47.51 ( 0.00%) 47.15 ( 0.76%) 47.98 ( -0.99%) 48.12 ( -1.28%) 49.56 ( -4.31%) 3.19.0 4.0.0-rc4 4.0.0-rc4 4.0.0-rc4 4.0.0-rc4 vanilla vanillavmwrite-v5r8preserve-v5r8slowscan-v5r8 User 46334.60 46391.94 44383.95 43971.89 44372.12 System 252.84 284.66 252.61 201.24 249.00 Elapsed 1062.14 1050.96 998.68 1000.94 1026.78 Overall the system CPU usage is comparable and the test is naturally a bit variable. The slowing of the scanner hurts numa01 but on this machine it is an adverse workload and patches that dramatically help it often hurt absolutely everything else. Due to patch 2, the fault activity is interesting 3.19.0 4.0.0-rc4 4.0.0-rc4 4.0.0-rc4 4.0.0-rc4 vanilla vanillavmwrite-v5r8preserve-v5r8slowscan-v5r8 Minor Faults 2097811 2656646 2597249 1981230 1636841 Major Faults 362 450 365 364 365 Note the impact preserving the write bit across protection updates and fault reduces faults. NUMA alloc hit 1229008 1217015 1191660 1178322 1199681 NUMA alloc miss 0 0 0 0 0 NUMA interleave hit 0 0 0 0 0 NUMA alloc local 1228514 1216317 1190871 1177448 1199021 NUMA base PTE updates 245706197 240041607 238195516 244704842 115012800 NUMA huge PMD updates 479530 468448 464868 477573 224487 NUMA page range updates 491225557 479886983 476207932 489222218 229950144 NUMA hint faults 659753 656503 641678 656926 294842 NUMA hint local faults 381604 373963 360478 337585 186249 NUMA hint local percent 57 56 56 51 63 NUMA pages migrated 5412140 6374899 6266530 5277468 5755096 AutoNUMA cost 5121% 5083% 4994% 5097% 2388% Here the impact of slowing the PTE scanner on migratrion failures is obvious as "NUMA base PTE updates" and "NUMA huge PMD updates" are massively reduced even though the headline performance is very similar. As xfsrepair was the reported workload here is the impact of the series on it. xfsrepair 3.19.0 4.0.0-rc4 4.0.0-rc4 4.0.0-rc4 4.0.0-rc4 vanilla vanilla vmwrite-v5r8 preserve-v5r8 slowscan-v5r8 Min real-fsmark 1183.29 ( 0.00%) 1165.73 ( 1.48%) 1152.78 ( 2.58%) 1153.64 ( 2.51%) 1177.62 ( 0.48%) Min syst-fsmark 4107.85 ( 0.00%) 4027.75 ( 1.95%) 3986.74 ( 2.95%) 3979.16 ( 3.13%) 4048.76 ( 1.44%) Min real-xfsrepair 441.51 ( 0.00%) 463.96 ( -5.08%) 449.50 ( -1.81%) 440.08 ( 0.32%) 439.87 ( 0.37%) Min syst-xfsrepair 195.76 ( 0.00%) 278.47 (-42.25%) 262.34 (-34.01%) 203.70 ( -4.06%) 143.64 ( 26.62%) Amean real-fsmark 1188.30 ( 0.00%) 1177.34 ( 0.92%) 1157.97 ( 2.55%) 1158.21 ( 2.53%) 1182.22 ( 0.51%) Amean syst-fsmark 4111.37 ( 0.00%) 4055.70 ( 1.35%) 3987.19 ( 3.02%) 3998.72 ( 2.74%) 4061.69 ( 1.21%) Amean real-xfsrepair 450.88 ( 0.00%) 468.32 ( -3.87%) 454.14 ( -0.72%) 442.36 ( 1.89%) 440.59 ( 2.28%) Amean syst-xfsrepair 199.66 ( 0.00%) 290.60 (-45.55%) 277.20 (-38.84%) 204.68 ( -2.51%) 150.55 ( 24.60%) Stddev real-fsmark 4.12 ( 0.00%) 10.82 (-162.29%) 4.14 ( -0.28%) 5.98 (-45.05%) 4.60 (-11.53%) Stddev syst-fsmark 2.63 ( 0.00%) 20.32 (-671.82%) 0.37 ( 85.89%) 16.47 (-525.59%) 15.05 (-471.79%) Stddev real-xfsrepair 6.87 ( 0.00%) 4.55 ( 33.75%) 3.46 ( 49.58%) 1.78 ( 74.12%) 0.52 ( 92.50%) Stddev syst-xfsrepair 3.02 ( 0.00%) 10.30 (-241.37%) 13.17 (-336.37%) 0.71 ( 76.63%) 5.00 (-65.61%) CoeffVar real-fsmark 0.35 ( 0.00%) 0.92 (-164.73%) 0.36 ( -2.91%) 0.52 (-48.82%) 0.39 (-12.10%) CoeffVar syst-fsmark 0.06 ( 0.00%) 0.50 (-682.41%) 0.01 ( 85.45%) 0.41 (-543.22%) 0.37 (-478.78%) CoeffVar real-xfsrepair 1.52 ( 0.00%) 0.97 ( 36.21%) 0.76 ( 49.94%) 0.40 ( 73.62%) 0.12 ( 92.33%) CoeffVar syst-xfsrepair 1.51 ( 0.00%) 3.54 (-134.54%) 4.75 (-214.31%) 0.34 ( 77.20%) 3.32 (-119.63%) Max real-fsmark 1193.39 ( 0.00%) 1191.77 ( 0.14%) 1162.90 ( 2.55%) 1166.66 ( 2.24%) 1188.50 ( 0.41%) Max syst-fsmark 4114.18 ( 0.00%) 4075.45 ( 0.94%) 3987.65 ( 3.08%) 4019.45 ( 2.30%) 4082.80 ( 0.76%) Max real-xfsrepair 457.80 ( 0.00%) 474.60 ( -3.67%) 457.82 ( -0.00%) 444.42 ( 2.92%) 441.03 ( 3.66%) Max syst-xfsrepair 203.11 ( 0.00%) 303.65 (-49.50%) 294.35 (-44.92%) 205.33 ( -1.09%) 155.28 ( 23.55%) The really relevant lines as syst-xfsrepair which is the system CPU usage when running xfsrepair. Note that on my machine the overhead was 45% higher on 4.0-rc4 which may be part of what Dave is seeing. Once we preserve the write bit across faults, it's only 2.51% higher on average. With the full series applied, system CPU usage is 24.6% lower on average. Again, the impact of preserving the write bit on minor faults is obvious and the impact of slowing scanning after migration failures is obvious on the PTE updates. Note also that the number of pages migrated is much reduced even though the headline performance is comparable. 3.19.0 4.0.0-rc4 4.0.0-rc4 4.0.0-rc4 4.0.0-rc4 vanilla vanillavmwrite-v5r8preserve-v5r8slowscan-v5r8 Minor Faults 153466827 254507978 249163829 153501373 105737890 Major Faults 610 702 690 649 724 NUMA base PTE updates 217735049 210756527 217729596 216937111 144344993 NUMA huge PMD updates 129294 85044 106921 127246 79887 NUMA pages migrated 21938995 29705270 28594162 22687324 16258075 3.19.0 4.0.0-rc4 4.0.0-rc4 4.0.0-rc4 4.0.0-rc4 vanilla vanillavmwrite-v5r8preserve-v5r8slowscan-v5r8 Mean sdb-avgqusz 13.47 2.54 2.55 2.47 2.49 Mean sdb-avgrqsz 202.32 140.22 139.50 139.02 138.12 Mean sdb-await 25.92 5.09 5.33 5.02 5.22 Mean sdb-r_await 4.71 0.19 0.83 0.51 0.11 Mean sdb-w_await 104.13 5.21 5.38 5.05 5.32 Mean sdb-svctm 0.59 0.13 0.14 0.13 0.14 Mean sdb-rrqm 0.16 0.00 0.00 0.00 0.00 Mean sdb-wrqm 3.59 1799.43 1826.84 1812.21 1785.67 Max sdb-avgqusz 111.06 12.13 14.05 11.66 15.60 Max sdb-avgrqsz 255.60 190.34 190.01 187.33 191.78 Max sdb-await 168.24 39.28 49.22 44.64 65.62 Max sdb-r_await 660.00 52.00 280.00 76.00 12.00 Max sdb-w_await 7804.00 39.28 49.22 44.64 65.62 Max sdb-svctm 4.00 2.82 2.86 1.98 2.84 Max sdb-rrqm 8.30 0.00 0.00 0.00 0.00 Max sdb-wrqm 34.20 5372.80 5278.60 5386.60 5546.15 FWIW, I also checked SPECjbb in different configurations but it's similar observations -- minor faults lower, PTE update activity lower and performance is roughly comparable against 3.19. This patch (of 3): Threads that share writable data within pages are grouped together as related tasks. This decision is based on whether the PTE is marked dirty which is subject to timing races between the PTE scanner update and when the application writes the page. If the page is file-backed, then background flushes and sync also affect placement. This is unpredictable behaviour which is impossible to reason about so this patch makes grouping decisions based on the VMA flags. Signed-off-by: Mel Gorman <mgorman@suse.de> Reported-by: Dave Chinner <david@fromorbit.com> Tested-by: Dave Chinner <david@fromorbit.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Aneesh Kumar <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Sergei Antonov authored
Fix B-tree corruption when a new record is inserted at position 0 in the node in hfs_brec_insert(). In this case a hfs_brec_update_parent() is called to update the parent index node (if exists) and it is passed hfs_find_data with a search_key containing a newly inserted key instead of the key to be updated. This results in an inconsistent index node. The bug reproduces on my machine after an extents overflow record for the catalog file (CNID=4) is inserted into the extents overflow B-tree. Because of a low (reserved) value of CNID=4, it has to become the first record in the first leaf node. The resulting first leaf node is correct: ---------------------------------------------------- | key0.CNID=4 | key1.CNID=123 | key2.CNID=456, ... | ---------------------------------------------------- But the parent index key0 still contains the previous key CNID=123: ----------------------- | key0.CNID=123 | ... | ----------------------- A change in hfs_brec_insert() makes hfs_brec_update_parent() work correctly by preventing it from getting fd->record=-1 value from __hfs_brec_find(). Along the way, I removed duplicate code with unification of the if condition. The resulting code is equivalent to the original code because node is never 0. Also hfs_brec_update_parent() will now return an error after getting a negative fd->record value. However, the return value of hfs_brec_update_parent() is not checked anywhere in the file and I'm leaving it unchanged by this patch. brec.c lacks error checking after some other calls too, but this issue is of less importance than the one being fixed by this patch. Signed-off-by: Sergei Antonov <saproj@gmail.com> Cc: Joe Perches <joe@perches.com> Reviewed-by: Vyacheslav Dubeyko <slava@dubeyko.com> Acked-by: Hin-Tak Leung <htl10@users.sourceforge.net> Cc: Anton Altaparmakov <aia21@cam.ac.uk> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@infradead.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Jean Delvare authored
I am familiar with these drivers and I care about them so let me add myself as their maintainer. Signed-off-by: Jean Delvare <jdelvare@suse.de> Acked-by: Matt Fleming <matt.fleming@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Taesoo Kim authored
When affs_bread_ino() fails, correctly unlock the page and release the page cache with proper error value. All write_end() should unlock/release the page that was locked by write_beg(). Signed-off-by: Taesoo Kim <tsgatesv@gmail.com> Cc: Fabian Frederick <fabf@skynet.be> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Jan Kara <jack@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Laura Abbott authored
Commit 3c605096 ("mm/page_alloc: restrict max order of merging on isolated pageblock") changed the logic of unset_migratetype_isolate to check the buddy allocator and explicitly call __free_pages to merge. The page that is being freed in this path never had prep_new_page called so set_page_refcounted is called explicitly but there is no call to kernel_map_pages. With the default kernel_map_pages this is mostly harmless but if kernel_map_pages does any manipulation of the page tables (unmapping or setting pages to read only) this may trigger a fault: alloc_contig_range test_pages_isolated(ceb00, ced00) failed Unable to handle kernel paging request at virtual address ffffffc0cec00000 pgd = ffffffc045fc4000 [ffffffc0cec00000] *pgd=0000000000000000 Internal error: Oops: 9600004f [#1] PREEMPT SMP Modules linked in: exfatfs CPU: 1 PID: 23237 Comm: TimedEventQueue Not tainted 3.10.49-gc72ad36-dirty #1 task: ffffffc03de52100 ti: ffffffc015388000 task.ti: ffffffc015388000 PC is at memset+0xc8/0x1c0 LR is at kernel_map_pages+0x1ec/0x244 Fix this by calling kernel_map_pages to ensure the page is set in the page table properly Fixes: 3c605096 ("mm/page_alloc: restrict max order of merging on isolated pageblock") Signed-off-by: Laura Abbott <lauraa@codeaurora.org> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Mel Gorman <mgorman@suse.de> Acked-by: Rik van Riel <riel@redhat.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: Xishi Qiu <qiuxishi@huawei.com> Cc: Vladimir Davydov <vdavydov@parallels.com> Acked-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Gioh Kim <gioh.kim@lge.com> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Mark Rutland authored
Commit 9aabf810 ("mm/slub: optimize alloc/free fastpath by removing preemption on/off") introduced an occasional hang for kernels built with CONFIG_PREEMPT && !CONFIG_SMP. The problem is the following loop the patch introduced to slab_alloc_node and slab_free: do { tid = this_cpu_read(s->cpu_slab->tid); c = raw_cpu_ptr(s->cpu_slab); } while (IS_ENABLED(CONFIG_PREEMPT) && unlikely(tid != c->tid)); GCC 4.9 has been observed to hoist the load of c and c->tid above the loop for !SMP kernels (as in this case raw_cpu_ptr(x) is compile-time constant and does not force a reload). On arm64 the generated assembly looks like: ldr x4, [x0,#8] loop: ldr x1, [x0,#8] cmp x1, x4 b.ne loop If the thread is preempted between the load of c->tid (into x1) and tid (into x4), and an allocation or free occurs in another thread (bumping the cpu_slab's tid), the thread will be stuck in the loop until s->cpu_slab->tid wraps, which may be forever in the absence of allocations/frees on the same CPU. This patch changes the loop condition to access c->tid with READ_ONCE. This ensures that the value is reloaded even when the compiler would otherwise assume it could cache the value, and also ensures that the load will not be torn. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Jesper Dangaard Brouer <brouer@redhat.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Steve Capper <steve.capper@linaro.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Gu Zheng authored
Qiu Xishi reported the following BUG when testing hot-add/hot-remove node under stress condition: BUG: unable to handle kernel paging request at 0000000000025f60 IP: next_online_pgdat+0x1/0x50 PGD 0 Oops: 0000 [#1] SMP ACPI: Device does not support D3cold Modules linked in: fuse nls_iso8859_1 nls_cp437 vfat fat loop dm_mod coretemp mperf crc32c_intel ghash_clmulni_intel aesni_intel ablk_helper cryptd lrw gf128mul glue_helper aes_x86_64 pcspkr microcode igb dca i2c_algo_bit ipv6 megaraid_sas iTCO_wdt i2c_i801 i2c_core iTCO_vendor_support tg3 sg hwmon ptp lpc_ich pps_core mfd_core acpi_pad rtc_cmos button ext3 jbd mbcache sd_mod crc_t10dif scsi_dh_alua scsi_dh_rdac scsi_dh_hp_sw scsi_dh_emc scsi_dh ahci libahci libata scsi_mod [last unloaded: rasf] CPU: 23 PID: 238 Comm: kworker/23:1 Tainted: G O 3.10.15-5885-euler0302 #1 Hardware name: HUAWEI TECHNOLOGIES CO.,LTD. Huawei N1/Huawei N1, BIOS V100R001 03/02/2015 Workqueue: events vmstat_update task: ffffa800d32c0000 ti: ffffa800d32ae000 task.ti: ffffa800d32ae000 RIP: 0010: next_online_pgdat+0x1/0x50 RSP: 0018:ffffa800d32afce8 EFLAGS: 00010286 RAX: 0000000000001440 RBX: ffffffff81da53b8 RCX: 0000000000000082 RDX: 0000000000000000 RSI: 0000000000000082 RDI: 0000000000000000 RBP: ffffa800d32afd28 R08: ffffffff81c93bfc R09: ffffffff81cbdc96 R10: 00000000000040ec R11: 00000000000000a0 R12: ffffa800fffb3440 R13: ffffa800d32afd38 R14: 0000000000000017 R15: ffffa800e6616800 FS: 0000000000000000(0000) GS:ffffa800e6600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000025f60 CR3: 0000000001a0b000 CR4: 00000000001407e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: refresh_cpu_vm_stats+0xd0/0x140 vmstat_update+0x11/0x50 process_one_work+0x194/0x3d0 worker_thread+0x12b/0x410 kthread+0xc6/0xd0 ret_from_fork+0x7c/0xb0 The cause is the "memset(pgdat, 0, sizeof(*pgdat))" at the end of try_offline_node, which will reset all the content of pgdat to 0, as the pgdat is accessed lock-free, so that the users still using the pgdat will panic, such as the vmstat_update routine. process A: offline node XX: vmstat_updat() refresh_cpu_vm_stats() for_each_populated_zone() find online node XX cond_resched() offline cpu and memory, then try_offline_node() node_set_offline(nid), and memset(pgdat, 0, sizeof(*pgdat)) zone = next_zone(zone) pg_data_t *pgdat = zone->zone_pgdat; // here pgdat is NULL now next_online_pgdat(pgdat) next_online_node(pgdat->node_id); // NULL pointer access So the solution here is postponing the reset of obsolete pgdat from try_offline_node() to hotadd_new_pgdat(), and just resetting pgdat->nr_zones and pgdat->classzone_idx to be 0 rather than the memset 0 to avoid breaking pointer information in pgdat. Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com> Reported-by: Xishi Qiu <qiuxishi@huawei.com> Suggested-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Taku Izumi <izumi.taku@jp.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Xie XiuQi <xiexiuqi@huawei.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Joe Perches authored
Commit c6a95dbe ("MAINTAINERS: add the RTC driver for the Armada38x") typoed the pattern, fix it. Signed-off-by: Joe Perches <joe@perches.com> Acked-by: Gregory CLEMENT <gregory.clement@free-electrons.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Naoya Horiguchi authored
walk_page_test() is purely pagewalk's internal stuff, and its positive return values are not intended to be passed to the callers of pagewalk. However, in the current code if the last vma in the do-while loop in walk_page_range() happens to return a positive value, it leaks outside walk_page_range(). So the user visible effect is invalid/unexpected return value (according to the reporter, mbind() causes it.) This patch fixes it simply by reinitializing the return value after checked. Another exposed interface, walk_page_vma(), already returns 0 for such cases so no problem. Fixes: fafaa426 ("pagewalk: improve vma handling") Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Signed-off-by: Kazutomo Yoshii <kazutomo.yoshii@gmail.com> Reported-by: Kazutomo Yoshii <kazutomo.yoshii@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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Leon Yu authored
I have constantly stumbled upon "kernel BUG at mm/rmap.c:399!" after upgrading to 3.19 and had no luck with 4.0-rc1 neither. So, after looking into new logic introduced by commit 7a3ef208 ("mm: prevent endless growth of anon_vma hierarchy"), I found chances are that unlink_anon_vmas() is called without incrementing dst->anon_vma->degree in anon_vma_clone() due to allocation failure. If dst->anon_vma is not NULL in error path, its degree will be incorrectly decremented in unlink_anon_vmas() and eventually underflow when exiting as a result of another call to unlink_anon_vmas(). That's how "kernel BUG at mm/rmap.c:399!" is triggered for me. This patch fixes the underflow by dropping dst->anon_vma when allocation fails. It's safe to do so regardless of original value of dst->anon_vma because dst->anon_vma doesn't have valid meaning if anon_vma_clone() fails. Besides, callers don't care dst->anon_vma in such case neither. Also suggested by Michal Hocko, we can clean up vma_adjust() a bit as anon_vma_clone() now does the work. [akpm@linux-foundation.org: tweak comment] Fixes: 7a3ef208 ("mm: prevent endless growth of anon_vma hierarchy") Signed-off-by: Leon Yu <chianglungyu@gmail.com> Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com> Reviewed-by: Michal Hocko <mhocko@suse.cz> Acked-by: Rik van Riel <riel@redhat.com> Acked-by: David Rientjes <rientjes@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Lars-Peter Clausen authored
The Moorestown RTC driver implements suspend and resume callbacks and assigns them to the suspend and resume fields of the device_driver struct. These callbacks are never actually called by anything though. Modify the driver to properly use dev_pm_ops so that the suspend and resume functions are actually executed upon suspend/resume. [akpm@linux-foundation.org: device_driver.name is const char *] Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: Feng Tang <feng.tang@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Ed Cashin authored
The coraid.com email address is defunct. The old aoe support area hosted at coraid.com is no longer up. These changes update the email and website to current ones. Signed-off-by: Ed Cashin <ed.cashin@acm.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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git://git.kernel.dk/linux-blockLinus Torvalds authored
Pull block layer fixes from Jens Axboe: "A small collection of fixes that has been gathered over the last few weeks. This contains: - A one-liner fix for NVMe, fixing a missing list_head init that could makes us oops on hitting recovery at load time. - Two small blk-mq fixes: - Fixup a bad goto jump on error handling. - Fix for oopsing if running out of reserved tags. - A memory leak fix for NBD. - Two small writeback fixes from Tejun, fixing a missing init to INITIAL_JIFFIES, and a possible underflow introduced recently. - A core merge fixup in sg gap detection, where rq->biotail was indexed with the count of rq->bio" * 'for-linus' of git://git.kernel.dk/linux-block: writeback: fix possible underflow in write bandwidth calculation NVMe: Initialize device list head before starting Fix bug in blk_rq_merge_ok blkmq: Fix NULL pointer deref when all reserved tags in blk-mq: fix use of incorrect goto label in blk_mq_init_queue error path nbd: fix possible memory leak writeback: add missing INITIAL_JIFFIES init in global_update_bandwidth()
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Heiko Carstens authored
After a suspend/resume cycle we missed to enable smt again, which leads to all sorts of bugs, since the kernel assumes smt is enabled, while the hardware thinks it is not. Reported-and-tested-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Reported-by: Stefan Haberland <stefan.haberland@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linuxLinus Torvalds authored
Pull two arm64 fixes from Catalin Marinas: - switch_mm() fix where init_mm.pgd ends up in the user TTBR0; swapper_pg_dir is not suitable for user mappings - this_cpu accessors fix for preemption safety * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64: percpu: Make this_cpu accessors pre-empt safe arm64: Use the reserved TTBR0 if context switching to the init_mm
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git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linuxLinus Torvalds authored
Pull powerpc fixes from Michael Ellerman: - Fix the MCE code to use CONFIG_KVM_BOOK3S_64_HANDLER - Little endian fixes for post mobility device tree update - Add PVR for POWER8NVL processor - Fixes for hypervisor doorbell handling * tag 'powerpc-4.0-3' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux: powerpc/book3s: Fix the MCE code to use CONFIG_KVM_BOOK3S_64_HANDLER powerpc/pseries: Little endian fixes for post mobility device tree update powerpc: Add PVR for POWER8NVL processor powerpc/powernv: Fixes for hypervisor doorbell handling
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git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds authored
Pull kvm fixes from Marcelo Tosatti: "Fix for higher-order page allocation failures, fix Xen-on-KVM with x2apic, L1 crash with unrestricted guest mode (nested VMX)" * git://git.kernel.org/pub/scm/virt/kvm/kvm: kvm: avoid page allocation failure in kvm_set_memory_region() KVM: x86: call irq notifiers with directed EOI KVM: nVMX: mask unrestricted_guest if disabled on L0
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git://git.kernel.org/pub/scm/linux/kernel/git/tj/libataLinus Torvalds authored
Pull libata fix from Tejun Heo: "One patch to fix a regression from the recent switch to blk-mq tag allocation which can cause oops on SAS-attached SATA drives" * 'for-4.0-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata: ata: Add a new flag to destinguish sas controller
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git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfdLinus Torvalds authored
Pull MFD fixes from Lee Jones: - Use DMA'able addresses for DMA; rtsx_usb - Use return value in the correct way; kempld-core * tag 'mfd-fixes-4.0' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd: mfd: kempld-core: Fix callback return value check mfd: rtsx_usb: Prevent DMA from stack
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- 24 Mar, 2015 6 commits
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git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spiLinus Torvalds authored
Pull spi fixes from Mark Brown: "A couple of driver specific fixes of the usual "important if you have that device" kind together with a fix for a use after free bug that was introduced into the trace code in some of the recent refactoring of the message queue handling" * tag 'spi-v4.0-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi: spi: trigger trace event for message-done before mesg->complete spi: dw-mid: clear BUSY flag fist and test other one spi: qup: Fix cs-num DT property parsing
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Linus Torvalds authored
Merge tag 'regulator-fix-v4.0-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator Pull regulator fixes from Mark Brown: "Two fixes here, one typo fix in the documentation and one fix for a system hang with one of the Palmas chips caused by the use of an incorrect offset being provided for one of the registers" * tag 'regulator-fix-v4.0-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator: regulator: Fix documentation for regmap in the config regulator: palmas: Correct TPS659038 register definition for REGEN2
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git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmapLinus Torvalds authored
Pull regmap fix from Mark Brown: "This patch fixes a bad interaction between the support that was added for having regmaps without devices for early system controller initialization and the trace support. There's a very good analysis of the actual issue in the commit message for the change" * tag 'regmap-fix-v4.0-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap: regmap: introduce regmap_name to fix syscon regmap trace events
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Steve Capper authored
this_cpu operations were implemented for arm64 in: 5284e1b4 arm64: xchg: Implement cmpxchg_double f97fc810 arm64: percpu: Implement this_cpu operations Unfortunately, it is possible for pre-emption to take place between address generation and data access. This can lead to cases where data is being manipulated by this_cpu for a different CPU than it was called on. Which effectively breaks the spec. This patch disables pre-emption for the this_cpu operations guaranteeing that address generation and data manipulation take place without a pre-emption in-between. Fixes: 5284e1b4 ("arm64: xchg: Implement cmpxchg_double") Fixes: f97fc810 ("arm64: percpu: Implement this_cpu operations") Reported-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Steve Capper <steve.capper@linaro.org> [catalin.marinas@arm.com: remove space after type cast] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
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Mark Brown authored
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Igor Mammedov authored
KVM guest can fail to startup with following trace on host: qemu-system-x86: page allocation failure: order:4, mode:0x40d0 Call Trace: dump_stack+0x47/0x67 warn_alloc_failed+0xee/0x150 __alloc_pages_direct_compact+0x14a/0x150 __alloc_pages_nodemask+0x776/0xb80 alloc_kmem_pages+0x3a/0x110 kmalloc_order+0x13/0x50 kmemdup+0x1b/0x40 __kvm_set_memory_region+0x24a/0x9f0 [kvm] kvm_set_ioapic+0x130/0x130 [kvm] kvm_set_memory_region+0x21/0x40 [kvm] kvm_vm_ioctl+0x43f/0x750 [kvm] Failure happens when attempting to allocate pages for 'struct kvm_memslots', however it doesn't have to be present in physically contiguous (kmalloc-ed) address space, change allocation to kvm_kvzalloc() so that it will be vmalloc-ed when its size is more then a page. Signed-off-by: Igor Mammedov <imammedo@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
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- 23 Mar, 2015 9 commits
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Radim Krčmář authored
kvm_ioapic_update_eoi() wasn't called if directed EOI was enabled. We need to do that for irq notifiers. (Like with edge interrupts.) Fix it by skipping EOI broadcast only. Bug: https://bugzilla.kernel.org/show_bug.cgi?id=82211Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Tested-by: Bandan Das <bsd@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
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Mark Brown authored
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Catalin Marinas authored
The idle_task_exit() function may call switch_mm() with next == &init_mm. On arm64, init_mm.pgd cannot be used for user mappings, so this patch simply sets the reserved TTBR0. Cc: <stable@vger.kernel.org> Reported-by: Jon Medhurst (Tixy) <tixy@linaro.org> Tested-by: Jon Medhurst (Tixy) <tixy@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
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git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds authored
Pull networking fixes from David Miller: 1) Validate iov ranges before feeding them into iov_iter_init(), from Al Viro. 2) We changed copy_from_msghdr_from_user() to zero out the msg_namelen is a NULL pointer is given for the msg_name. Do the same in the compat code too. From Catalin Marinas. 3) Fix partially initialized tuples in netfilter conntrack helper, from Ian Wilson. 4) Missing continue; statement in nft_hash walker can lead to crashes, from Herbert Xu. 5) tproxy_tg6_check looks for IP6T_INV_PROTO in ->flags instead of ->invflags, fix from Pablo Neira Ayuso. 6) Incorrect memory account of TCP FINs can result in negative socket memory accounting values. Fix from Josh Hunt. 7) Don't allow virtual functions to enable VLAN promiscuous mode in be2net driver, from Vasundhara Volam. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: netfilter: nft_compat: set IP6T_F_PROTO flag if protocol is set cx82310_eth: wait for firmware to become ready net: validate the range we feed to iov_iter_init() in sys_sendto/sys_recvfrom net: compat: Update get_compat_msghdr() to match copy_msghdr_from_user() behaviour be2net: use PCI MMIO read instead of config read for errors be2net: restrict MODIFY_EQ_DELAY cmd to a max of 8 EQs be2net: Prevent VFs from enabling VLAN promiscuous mode tcp: fix tcp fin memory accounting ipv6: fix backtracking for throw routes net: ethernet: pcnet32: Setup the SRAM and NOUFLO on Am79C97{3, 5} ipv6: call ipv6_proxy_select_ident instead of ipv6_select_ident in udp6_ufo_fragment netfilter: xt_TPROXY: fix invflags check in tproxy_tg6_check() netfilter: restore rule tracing via nfnetlink_log netfilter: nf_tables: allow to change chain policy without hook if it exists netfilter: Fix potential crash in nft_hash walker netfilter: Zero the tuple in nfnl_cthelper_parse_tuple()
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git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparcLinus Torvalds authored
Pull sparc fixes from David Miller: "Some perf bug fixes from David Ahern, and the fix for that nasty memmove() bug" * git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc: sparc64: Fix several bugs in memmove(). sparc: Touch NMI watchdog when walking cpus and calling printk sparc: perf: Add support M7 processor sparc: perf: Make counting mode actually work sparc: perf: Remove redundant perf_pmu_{en|dis}able calls
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David S. Miller authored
Firstly, handle zero length calls properly. Believe it or not there are a few of these happening during early boot. Next, we can't just drop to a memcpy() call in the forward copy case where dst <= src. The reason is that the cache initializing stores used in the Niagara memcpy() implementations can end up clearing out cache lines before we've sourced their original contents completely. For example, considering NG4memcpy, the main unrolled loop begins like this: load src + 0x00 load src + 0x08 load src + 0x10 load src + 0x18 load src + 0x20 store dst + 0x00 Assume dst is 64 byte aligned and let's say that dst is src - 8 for this memcpy() call. That store at the end there is the one to the first line in the cache line, thus clearing the whole line, which thus clobbers "src + 0x28" before it even gets loaded. To avoid this, just fall through to a simple copy only mildly optimized for the case where src and dst are 8 byte aligned and the length is a multiple of 8 as well. We could get fancy and call GENmemcpy() but this is good enough for how this thing is actually used. Reported-by: David Ahern <david.ahern@oracle.com> Reported-by: Bob Picco <bpicco@meloft.net> Signed-off-by: David S. Miller <davem@davemloft.net>
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Tejun Heo authored
From 1ebf33901ecc75d9496862dceb1ef0377980587c Mon Sep 17 00:00:00 2001 From: Tejun Heo <tj@kernel.org> Date: Mon, 23 Mar 2015 00:08:19 -0400 2f800fbd ("writeback: fix dirtied pages accounting on redirty") introduced account_page_redirty() which reverts stat updates for a redirtied page, making BDI_DIRTIED no longer monotonically increasing. bdi_update_write_bandwidth() uses the delta in BDI_DIRTIED as the basis for bandwidth calculation. While unlikely, since the above patch, the newer value may be lower than the recorded past value and underflow the bandwidth calculation leading to a wild result. Fix it by subtracing min of the old and new values when calculating delta. AFAIK, there hasn't been any report of it happening but the resulting erratic behavior would be non-critical and temporary, so it's possible that the issue is happening without being reported. The risk of the fix is very low, so tagged for -stable. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Jan Kara <jack@suse.cz> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Greg Thelen <gthelen@google.com> Fixes: 2f800fbd ("writeback: fix dirtied pages accounting on redirty") Cc: stable@vger.kernel.org Signed-off-by: Jens Axboe <axboe@fb.com>
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Keith Busch authored
Driver recovery requires the device's list node to have been initialized. Fixes: https://lkml.org/lkml/2015/3/22/262Reported-by: Steven Noonan <steven@uplinklabs.net> Signed-off-by: Keith Busch <keith.busch@intel.com> Cc: Matthew Wilcox <willy@linux.intel.com> Cc: Jens Axboe <axboe@fb.com> Signed-off-by: Jens Axboe <axboe@fb.com>
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James Hogan authored
When ioremap_wc() or ioremap_cached() are used without first including asm/pgtable.h, the _PAGE_CACHEABLE or _PAGE_WR_COMBINE definitions aren't found, resulting in build errors like the following (in next-20150323 due to "lib: devres: add a helper function for ioremap_wc"): lib/devres.c: In function ‘devm_ioremap_wc’: lib/devres.c:91: error: ‘_PAGE_WR_COMBINE’ undeclared We can't easily include asm/pgtable.h in asm/io.h due to dependency problems, so split out the _PAGE_* definitions from asm/pgtable.h into a separate asm/pgtable-bits.h header (as a couple of other architectures already do), and include that in io.h instead. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: linux-metag@vger.kernel.org Cc: Abhilash Kesavan <a.kesavan@samsung.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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