- 02 Mar, 2015 40 commits
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Vlastimil Babka authored
commit 99592d59 upstream. When studying page stealing, I noticed some weird looking decisions in try_to_steal_freepages(). The first I assume is a bug (Patch 1), the following two patches were driven by evaluation. Testing was done with stress-highalloc of mmtests, using the mm_page_alloc_extfrag tracepoint and postprocessing to get counts of how often page stealing occurs for individual migratetypes, and what migratetypes are used for fallbacks. Arguably, the worst case of page stealing is when UNMOVABLE allocation steals from MOVABLE pageblock. RECLAIMABLE allocation stealing from MOVABLE allocation is also not ideal, so the goal is to minimize these two cases. The evaluation of v2 wasn't always clear win and Joonsoo questioned the results. Here I used different baseline which includes RFC compaction improvements from [1]. I found that the compaction improvements reduce variability of stress-highalloc, so there's less noise in the data. First, let's look at stress-highalloc configured to do sync compaction, and how these patches reduce page stealing events during the test. First column is after fresh reboot, other two are reiterations of test without reboot. That was all accumulater over 5 re-iterations (so the benchmark was run 5x3 times with 5 fresh restarts). Baseline: 3.19-rc4 3.19-rc4 3.19-rc4 5-nothp-1 5-nothp-2 5-nothp-3 Page alloc extfrag event 10264225 8702233 10244125 Extfrag fragmenting 10263271 8701552 10243473 Extfrag fragmenting for unmovable 13595 17616 15960 Extfrag fragmenting unmovable placed with movable 7989 12193 8447 Extfrag fragmenting for reclaimable 658 1840 1817 Extfrag fragmenting reclaimable placed with movable 558 1677 1679 Extfrag fragmenting for movable 10249018 8682096 10225696 With Patch 1: 3.19-rc4 3.19-rc4 3.19-rc4 6-nothp-1 6-nothp-2 6-nothp-3 Page alloc extfrag event 11834954 9877523 9774860 Extfrag fragmenting 11833993 9876880 9774245 Extfrag fragmenting for unmovable 7342 16129 11712 Extfrag fragmenting unmovable placed with movable 4191 10547 6270 Extfrag fragmenting for reclaimable 373 1130 923 Extfrag fragmenting reclaimable placed with movable 302 906 738 Extfrag fragmenting for movable 11826278 9859621 9761610 With Patch 2: 3.19-rc4 3.19-rc4 3.19-rc4 7-nothp-1 7-nothp-2 7-nothp-3 Page alloc extfrag event 4725990 3668793 3807436 Extfrag fragmenting 4725104 3668252 3806898 Extfrag fragmenting for unmovable 6678 7974 7281 Extfrag fragmenting unmovable placed with movable 2051 3829 4017 Extfrag fragmenting for reclaimable 429 1208 1278 Extfrag fragmenting reclaimable placed with movable 369 976 1034 Extfrag fragmenting for movable 4717997 3659070 3798339 With Patch 3: 3.19-rc4 3.19-rc4 3.19-rc4 8-nothp-1 8-nothp-2 8-nothp-3 Page alloc extfrag event 5016183 4700142 3850633 Extfrag fragmenting 5015325 4699613 3850072 Extfrag fragmenting for unmovable 1312 3154 3088 Extfrag fragmenting unmovable placed with movable 1115 2777 2714 Extfrag fragmenting for reclaimable 437 1193 1097 Extfrag fragmenting reclaimable placed with movable 330 969 879 Extfrag fragmenting for movable 5013576 4695266 3845887 In v2 we've seen apparent regression with Patch 1 for unmovable events, this is now gone, suggesting it was indeed noise. Here, each patch improves the situation for unmovable events. Reclaimable is improved by patch 1 and then either the same modulo noise, or perhaps sligtly worse - a small price for unmovable improvements, IMHO. The number of movable allocations falling back to other migratetypes is most noisy, but it's reduced to half at Patch 2 nevertheless. These are least critical as compaction can move them around. If we look at success rates, the patches don't affect them, that didn't change. Baseline: 3.19-rc4 3.19-rc4 3.19-rc4 5-nothp-1 5-nothp-2 5-nothp-3 Success 1 Min 49.00 ( 0.00%) 42.00 ( 14.29%) 41.00 ( 16.33%) Success 1 Mean 51.00 ( 0.00%) 45.00 ( 11.76%) 42.60 ( 16.47%) Success 1 Max 55.00 ( 0.00%) 51.00 ( 7.27%) 46.00 ( 16.36%) Success 2 Min 53.00 ( 0.00%) 47.00 ( 11.32%) 44.00 ( 16.98%) Success 2 Mean 59.60 ( 0.00%) 50.80 ( 14.77%) 48.20 ( 19.13%) Success 2 Max 64.00 ( 0.00%) 56.00 ( 12.50%) 52.00 ( 18.75%) Success 3 Min 84.00 ( 0.00%) 82.00 ( 2.38%) 78.00 ( 7.14%) Success 3 Mean 85.60 ( 0.00%) 82.80 ( 3.27%) 79.40 ( 7.24%) Success 3 Max 86.00 ( 0.00%) 83.00 ( 3.49%) 80.00 ( 6.98%) Patch 1: 3.19-rc4 3.19-rc4 3.19-rc4 6-nothp-1 6-nothp-2 6-nothp-3 Success 1 Min 49.00 ( 0.00%) 44.00 ( 10.20%) 44.00 ( 10.20%) Success 1 Mean 51.80 ( 0.00%) 46.00 ( 11.20%) 45.80 ( 11.58%) Success 1 Max 54.00 ( 0.00%) 49.00 ( 9.26%) 49.00 ( 9.26%) Success 2 Min 58.00 ( 0.00%) 49.00 ( 15.52%) 48.00 ( 17.24%) Success 2 Mean 60.40 ( 0.00%) 51.80 ( 14.24%) 50.80 ( 15.89%) Success 2 Max 63.00 ( 0.00%) 54.00 ( 14.29%) 55.00 ( 12.70%) Success 3 Min 84.00 ( 0.00%) 81.00 ( 3.57%) 79.00 ( 5.95%) Success 3 Mean 85.00 ( 0.00%) 81.60 ( 4.00%) 79.80 ( 6.12%) Success 3 Max 86.00 ( 0.00%) 82.00 ( 4.65%) 82.00 ( 4.65%) Patch 2: 3.19-rc4 3.19-rc4 3.19-rc4 7-nothp-1 7-nothp-2 7-nothp-3 Success 1 Min 50.00 ( 0.00%) 44.00 ( 12.00%) 39.00 ( 22.00%) Success 1 Mean 52.80 ( 0.00%) 45.60 ( 13.64%) 42.40 ( 19.70%) Success 1 Max 55.00 ( 0.00%) 46.00 ( 16.36%) 47.00 ( 14.55%) Success 2 Min 52.00 ( 0.00%) 48.00 ( 7.69%) 45.00 ( 13.46%) Success 2 Mean 53.40 ( 0.00%) 49.80 ( 6.74%) 48.80 ( 8.61%) Success 2 Max 57.00 ( 0.00%) 52.00 ( 8.77%) 52.00 ( 8.77%) Success 3 Min 84.00 ( 0.00%) 81.00 ( 3.57%) 79.00 ( 5.95%) Success 3 Mean 85.00 ( 0.00%) 82.40 ( 3.06%) 79.60 ( 6.35%) Success 3 Max 86.00 ( 0.00%) 83.00 ( 3.49%) 80.00 ( 6.98%) Patch 3: 3.19-rc4 3.19-rc4 3.19-rc4 8-nothp-1 8-nothp-2 8-nothp-3 Success 1 Min 46.00 ( 0.00%) 44.00 ( 4.35%) 42.00 ( 8.70%) Success 1 Mean 50.20 ( 0.00%) 45.60 ( 9.16%) 44.00 ( 12.35%) Success 1 Max 52.00 ( 0.00%) 47.00 ( 9.62%) 47.00 ( 9.62%) Success 2 Min 53.00 ( 0.00%) 49.00 ( 7.55%) 48.00 ( 9.43%) Success 2 Mean 55.80 ( 0.00%) 50.60 ( 9.32%) 49.00 ( 12.19%) Success 2 Max 59.00 ( 0.00%) 52.00 ( 11.86%) 51.00 ( 13.56%) Success 3 Min 84.00 ( 0.00%) 80.00 ( 4.76%) 79.00 ( 5.95%) Success 3 Mean 85.40 ( 0.00%) 81.60 ( 4.45%) 80.40 ( 5.85%) Success 3 Max 87.00 ( 0.00%) 83.00 ( 4.60%) 82.00 ( 5.75%) While there's no improvement here, I consider reduced fragmentation events to be worth on its own. Patch 2 also seems to reduce scanning for free pages, and migrations in compaction, suggesting it has somewhat less work to do: Patch 1: Compaction stalls 4153 3959 3978 Compaction success 1523 1441 1446 Compaction failures 2630 2517 2531 Page migrate success 4600827 4943120 5104348 Page migrate failure 19763 16656 17806 Compaction pages isolated 9597640 10305617 10653541 Compaction migrate scanned 77828948 86533283 87137064 Compaction free scanned 517758295 521312840 521462251 Compaction cost 5503 5932 6110 Patch 2: Compaction stalls 3800 3450 3518 Compaction success 1421 1316 1317 Compaction failures 2379 2134 2201 Page migrate success 4160421 4502708 4752148 Page migrate failure 19705 14340 14911 Compaction pages isolated 8731983 9382374 9910043 Compaction migrate scanned 98362797 96349194 98609686 Compaction free scanned 496512560 469502017 480442545 Compaction cost 5173 5526 5811 As with v2, /proc/pagetypeinfo appears unaffected with respect to numbers of unmovable and reclaimable pageblocks. Configuring the benchmark to allocate like THP page fault (i.e. no sync compaction) gives much noisier results for iterations 2 and 3 after reboot. This is not so surprising given how [1] offers lower improvements in this scenario due to less restarts after deferred compaction which would change compaction pivot. Baseline: 3.19-rc4 3.19-rc4 3.19-rc4 5-thp-1 5-thp-2 5-thp-3 Page alloc extfrag event 8148965 6227815 6646741 Extfrag fragmenting 8147872 6227130 6646117 Extfrag fragmenting for unmovable 10324 12942 15975 Extfrag fragmenting unmovable placed with movable 5972 8495 10907 Extfrag fragmenting for reclaimable 601 1707 2210 Extfrag fragmenting reclaimable placed with movable 520 1570 2000 Extfrag fragmenting for movable 8136947 6212481 6627932 Patch 1: 3.19-rc4 3.19-rc4 3.19-rc4 6-thp-1 6-thp-2 6-thp-3 Page alloc extfrag event 8345457 7574471 7020419 Extfrag fragmenting 8343546 7573777 7019718 Extfrag fragmenting for unmovable 10256 18535 30716 Extfrag fragmenting unmovable placed with movable 6893 11726 22181 Extfrag fragmenting for reclaimable 465 1208 1023 Extfrag fragmenting reclaimable placed with movable 353 996 843 Extfrag fragmenting for movable 8332825 7554034 6987979 Patch 2: 3.19-rc4 3.19-rc4 3.19-rc4 7-thp-1 7-thp-2 7-thp-3 Page alloc extfrag event 3512847 3020756 2891625 Extfrag fragmenting 3511940 3020185 2891059 Extfrag fragmenting for unmovable 9017 6892 6191 Extfrag fragmenting unmovable placed with movable 1524 3053 2435 Extfrag fragmenting for reclaimable 445 1081 1160 Extfrag fragmenting reclaimable placed with movable 375 918 986 Extfrag fragmenting for movable 3502478 3012212 2883708 Patch 3: 3.19-rc4 3.19-rc4 3.19-rc4 8-thp-1 8-thp-2 8-thp-3 Page alloc extfrag event 3181699 3082881 2674164 Extfrag fragmenting 3180812 3082303 2673611 Extfrag fragmenting for unmovable 1201 4031 4040 Extfrag fragmenting unmovable placed with movable 974 3611 3645 Extfrag fragmenting for reclaimable 478 1165 1294 Extfrag fragmenting reclaimable placed with movable 387 985 1030 Extfrag fragmenting for movable 3179133 3077107 2668277 The improvements for first iteration are clear, the rest is much noisier and can appear like regression for Patch 1. Anyway, patch 2 rectifies it. Allocation success rates are again unaffected so there's no point in making this e-mail any longer. [1] http://marc.info/?l=linux-mm&m=142166196321125&w=2 This patch (of 3): When __rmqueue_fallback() is called to allocate a page of order X, it will find a page of order Y >= X of a fallback migratetype, which is different from the desired migratetype. With the help of try_to_steal_freepages(), it may change the migratetype (to the desired one) also of: 1) all currently free pages in the pageblock containing the fallback page 2) the fallback pageblock itself 3) buddy pages created by splitting the fallback page (when Y > X) These decisions take the order Y into account, as well as the desired migratetype, with the goal of preventing multiple fallback allocations that could e.g. distribute UNMOVABLE allocations among multiple pageblocks. Originally, decision for 1) has implied the decision for 3). Commit 47118af0 ("mm: mmzone: MIGRATE_CMA migration type added") changed that (probably unintentionally) so that the buddy pages in case 3) are always changed to the desired migratetype, except for CMA pageblocks. Commit fef903ef ("mm/page_allo.c: restructure free-page stealing code and fix a bug") did some refactoring and added a comment that the case of 3) is intended. Commit 0cbef29a ("mm: __rmqueue_fallback() should respect pageblock type") removed the comment and tried to restore the original behavior where 1) implies 3), but due to the previous refactoring, the result is instead that only 2) implies 3) - and the conditions for 2) are less frequently met than conditions for 1). This may increase fragmentation in situations where the code decides to steal all free pages from the pageblock (case 1)), but then gives back the buddy pages produced by splitting. This patch restores the original intended logic where 1) implies 3). During testing with stress-highalloc from mmtests, this has shown to decrease the number of events where UNMOVABLE and RECLAIMABLE allocations steal from MOVABLE pageblocks, which can lead to permanent fragmentation. In some cases it has increased the number of events when MOVABLE allocations steal from UNMOVABLE or RECLAIMABLE pageblocks, but these are fixable by sync compaction and thus less harmful. Note that evaluation has shown that the behavior introduced by 47118af0 for buddy pages in case 3) is actually even better than the original logic, so the following patch will introduce it properly once again. For stable backports of this patch it makes thus sense to only fix versions containing 0cbef29a. [iamjoonsoo.kim@lge.com: tracepoint fix] Signed-off-by:
Vlastimil Babka <vbabka@suse.cz> Acked-by:
Mel Gorman <mgorman@suse.de> Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Acked-by:
Minchan Kim <minchan@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Rik van Riel <riel@redhat.com> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by:
Luis Henriques <luis.henriques@canonical.com>
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Naoya Horiguchi authored
commit 9fbc1f63 upstream. If __unmap_hugepage_range() tries to unmap the address range over which hugepage migration is on the way, we get the wrong page because pte_page() doesn't work for migration entries. This patch simply clears the pte for migration entries as we do for hwpoison entries. Fixes: 290408d4 ("hugetlb: hugepage migration core") Signed-off-by:
Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Hugh Dickins <hughd@google.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: David Rientjes <rientjes@google.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Rik van Riel <riel@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Luiz Capitulino <lcapitulino@redhat.com> Cc: Nishanth Aravamudan <nacc@linux.vnet.ibm.com> Cc: Lee Schermerhorn <lee.schermerhorn@hp.com> Cc: Steve Capper <steve.capper@linaro.org> Signed-off-by:
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Naoya Horiguchi authored
commit a8bda28d upstream. There is a race condition between hugepage migration and change_protection(), where hugetlb_change_protection() doesn't care about migration entries and wrongly overwrites them. That causes unexpected results like kernel crash. HWPoison entries also can cause the same problem. This patch adds is_hugetlb_entry_(migration|hwpoisoned) check in this function to do proper actions. Fixes: 290408d4 ("hugetlb: hugepage migration core") Signed-off-by:
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Naoya Horiguchi authored
commit 0f792cf9 upstream. When running the test which causes the race as shown in the previous patch, we can hit the BUG "get_page() on refcount 0 page" in hugetlb_fault(). This race happens when pte turns into migration entry just after the first check of is_hugetlb_entry_migration() in hugetlb_fault() passed with false. To fix this, we need to check pte_present() again after huge_ptep_get(). This patch also reorders taking ptl and doing pte_page(), because pte_page() should be done in ptl. Due to this reordering, we need use trylock_page() in page != pagecache_page case to respect locking order. Fixes: 66aebce7 ("hugetlb: fix race condition in hugetlb_fault()") Signed-off-by:
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Naoya Horiguchi authored
commit e66f17ff upstream. We have a race condition between move_pages() and freeing hugepages, where move_pages() calls follow_page(FOLL_GET) for hugepages internally and tries to get its refcount without preventing concurrent freeing. This race crashes the kernel, so this patch fixes it by moving FOLL_GET code for hugepages into follow_huge_pmd() with taking the page table lock. This patch intentionally removes page==NULL check after pte_page. This is justified because pte_page() never returns NULL for any architectures or configurations. This patch changes the behavior of follow_huge_pmd() for tail pages and then tail pages can be pinned/returned. So the caller must be changed to properly handle the returned tail pages. We could have a choice to add the similar locking to follow_huge_(addr|pud) for consistency, but it's not necessary because currently these functions don't support FOLL_GET flag, so let's leave it for future development. Here is the reproducer: $ cat movepages.c #include <stdio.h> #include <stdlib.h> #include <numaif.h> #define ADDR_INPUT 0x700000000000UL #define HPS 0x200000 #define PS 0x1000 int main(int argc, char *argv[]) { int i; int nr_hp = strtol(argv[1], NULL, 0); int nr_p = nr_hp * HPS / PS; int ret; void **addrs; int *status; int *nodes; pid_t pid; pid = strtol(argv[2], NULL, 0); addrs = malloc(sizeof(char *) * nr_p + 1); status = malloc(sizeof(char *) * nr_p + 1); nodes = malloc(sizeof(char *) * nr_p + 1); while (1) { for (i = 0; i < nr_p; i++) { addrs[i] = (void *)ADDR_INPUT + i * PS; nodes[i] = 1; status[i] = 0; } ret = numa_move_pages(pid, nr_p, addrs, nodes, status, MPOL_MF_MOVE_ALL); if (ret == -1) err("move_pages"); for (i = 0; i < nr_p; i++) { addrs[i] = (void *)ADDR_INPUT + i * PS; nodes[i] = 0; status[i] = 0; } ret = numa_move_pages(pid, nr_p, addrs, nodes, status, MPOL_MF_MOVE_ALL); if (ret == -1) err("move_pages"); } return 0; } $ cat hugepage.c #include <stdio.h> #include <sys/mman.h> #include <string.h> #define ADDR_INPUT 0x700000000000UL #define HPS 0x200000 int main(int argc, char *argv[]) { int nr_hp = strtol(argv[1], NULL, 0); char *p; while (1) { p = mmap((void *)ADDR_INPUT, nr_hp * HPS, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB, -1, 0); if (p != (void *)ADDR_INPUT) { perror("mmap"); break; } memset(p, 0, nr_hp * HPS); munmap(p, nr_hp * HPS); } } $ sysctl vm.nr_hugepages=40 $ ./hugepage 10 & $ ./movepages 10 $(pgrep -f hugepage) Fixes: e632a938 ("mm: migrate: add hugepage migration code to move_pages()") Signed-off-by:
Hugh Dickins <hughd@google.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: David Rientjes <rientjes@google.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Rik van Riel <riel@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Luiz Capitulino <lcapitulino@redhat.com> Cc: Nishanth Aravamudan <nacc@linux.vnet.ibm.com> Cc: Lee Schermerhorn <lee.schermerhorn@hp.com> Cc: Steve Capper <steve.capper@linaro.org> Signed-off-by:
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Naoya Horiguchi authored
commit cbef8478 upstream. Migrating hugepages and hwpoisoned hugepages are considered as non-present hugepages, and they are referenced via migration entries and hwpoison entries in their page table slots. This behavior causes race condition because pmd_huge() doesn't tell non-huge pages from migrating/hwpoisoned hugepages. follow_page_mask() is one example where the kernel would call follow_page_pte() for such hugepage while this function is supposed to handle only normal pages. To avoid this, this patch makes pmd_huge() return true when pmd_none() is true *and* pmd_present() is false. We don't have to worry about mixing up non-present pmd entry with normal pmd (pointing to leaf level pte entry) because pmd_present() is true in normal pmd. The same race condition could happen in (x86-specific) gup_pmd_range(), where this patch simply adds pmd_present() check instead of pmd_huge(). This is because gup_pmd_range() is fast path. If we have non-present hugepage in this function, we will go into gup_huge_pmd(), then return 0 at flag mask check, and finally fall back to the slow path. Fixes: 290408d4 ("hugetlb: hugepage migration core") Signed-off-by:
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Mikulas Patocka authored
commit d4d4eda2 upstream. On Dell Latitude C600 laptop with Pentium 3 850MHz processor, the speedstep-smi driver sometimes loads and sometimes doesn't load with "change to state X failed" message. The hardware sometimes refuses to change frequency and in this case, we need to retry later. I found out that we need to enable interrupts while waiting. When we enable interrupts, the hardware blockage that prevents frequency transition resolves and the transition is possible. With disabled interrupts, the blockage doesn't resolve (no matter how long do we wait). The exact reasons for this hardware behavior are unknown. This patch enables interrupts in the function speedstep_set_state that can be called with disabled interrupts. However, this function is called with disabled interrupts only from speedstep_get_freqs, so it shouldn't cause any problem. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com Acked-by:
Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by:
Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by:
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Trond Myklebust authored
commit d8ba1f97 upstream. If the call to decode_rc_list() fails due to a memory allocation error, then we need to truncate the array size to ensure that we only call kfree() on those pointer that were allocated. Reported-by:
David Ramos <daramos@stanford.edu> Fixes: 4aece6a1 ("nfs41: cb_sequence xdr implementation") Signed-off-by:
Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by:
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Alex Deucher authored
commit 410af8d7 upstream. Enable at init and disable on fini. Workaround for hardware problems. v2 (chk): extend commit message v3: add new function Signed-off-by:
Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Christian König <christian.koenig@amd.com> (v2) Signed-off-by:
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Christian König authored
commit a9c73a0e upstream. Emit the EOP twice to avoid cache flushing problems. Signed-off-by:
Christian König <christian.koenig@amd.com> Signed-off-by:
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Tony Battersby authored
commit 564e559f upstream. If the allocation of bt->bs fails, then bt->map can be freed twice, once in blk_mq_init_bitmap_tags() -> bt_alloc(), and once in blk_mq_init_bitmap_tags() -> bt_free(). Fix by setting the pointer to NULL after the first free. Signed-off-by:
Tony Battersby <tonyb@cybernetics.com> Signed-off-by:
Jens Axboe <axboe@fb.com> Signed-off-by:
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Steven Rostedt (Red Hat) authored
commit 1e0d6714 upstream. When an application connects to the ring buffer via splice, it can only read full pages. Splice does not work with partial pages. If there is not enough data to fill a page, the splice command will either block or return -EAGAIN (if set to nonblock). Code was added where if the page is not full, to just sleep again. The problem is, it will get woken up again on the next event. That is, when something is written into the ring buffer, if there is a waiter it will wake it up. The waiter would then check the buffer, see that it still does not have enough data to fill a page and go back to sleep. To make matters worse, when the waiter goes back to sleep, it could cause another event, which would wake it back up again to see it doesn't have enough data and sleep again. This produces a tremendous overhead and fills the ring buffer with noise. For example, recording sched_switch on an idle system for 10 seconds produces 25,350,475 events!!! Create another wait queue for those waiters wanting full pages. When an event is written, it only wakes up waiters if there's a full page of data. It does not wake up the waiter if the page is not yet full. After this change, recording sched_switch on an idle system for 10 seconds produces only 800 events. Getting rid of 25,349,675 useless events (99.9969% of events!!), is something to take seriously. Cc: Rabin Vincent <rabin@rab.in> Fixes: e30f53aa "tracing: Do not busy wait in buffer splice" Signed-off-by:
Steven Rostedt <rostedt@goodmis.org> Signed-off-by:
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Jan Kara authored
commit 6ee8e25f upstream. Commit e9fd702a ("audit: convert audit watches to use fsnotify instead of inotify") broke handling of renames in audit. Audit code wants to update inode number of an inode corresponding to watched name in a directory. When something gets renamed into a directory to a watched name, inotify previously passed moved inode to audit code however new fsnotify code passes directory inode where the change happened. That confuses audit and it starts watching parent directory instead of a file in a directory. This can be observed for example by doing: cd /tmp touch foo bar auditctl -w /tmp/foo touch foo mv bar foo touch foo In audit log we see events like: type=CONFIG_CHANGE msg=audit(1423563584.155:90): auid=1000 ses=2 op="updated rules" path="/tmp/foo" key=(null) list=4 res=1 ... type=PATH msg=audit(1423563584.155:91): item=2 name="bar" inode=1046884 dev=08:0 2 mode=0100644 ouid=0 ogid=0 rdev=00:00 nametype=DELETE type=PATH msg=audit(1423563584.155:91): item=3 name="foo" inode=1046842 dev=08:0 2 mode=0100644 ouid=0 ogid=0 rdev=00:00 nametype=DELETE type=PATH msg=audit(1423563584.155:91): item=4 name="foo" inode=1046884 dev=08:0 2 mode=0100644 ouid=0 ogid=0 rdev=00:00 nametype=CREATE ... and that's it - we see event for the first touch after creating the audit rule, we see events for rename but we don't see any event for the last touch. However we start seeing events for unrelated stuff happening in /tmp. Fix the problem by passing moved inode as data in the FS_MOVED_FROM and FS_MOVED_TO events instead of the directory where the change happens. This doesn't introduce any new problems because noone besides audit_watch.c cares about the passed value: fs/notify/fanotify/fanotify.c cares only about FSNOTIFY_EVENT_PATH events. fs/notify/dnotify/dnotify.c doesn't care about passed 'data' value at all. fs/notify/inotify/inotify_fsnotify.c uses 'data' only for FSNOTIFY_EVENT_PATH. kernel/audit_tree.c doesn't care about passed 'data' at all. kernel/audit_watch.c expects moved inode as 'data'. Fixes: e9fd702a ("audit: convert audit watches to use fsnotify instead of inotify") Signed-off-by:
Jan Kara <jack@suse.cz> Cc: Paul Moore <paul@paul-moore.com> Cc: Eric Paris <eparis@redhat.com> Signed-off-by:
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Vikram Mulukutla authored
commit 7215853e upstream. Commit 6edb2a8a introduced an array map_pages that contains the addresses returned by kmap_atomic. However, when unmapping those pages, map_pages[0] is unmapped before map_pages[1], breaking the nesting requirement as specified in the documentation for kmap_atomic/kunmap_atomic. This was caught by the highmem debug code present in kunmap_atomic. Fix the loop to do the unmapping properly. Link: http://lkml.kernel.org/r/1418871056-6614-1-git-send-email-markivx@codeaurora.orgReviewed-by:
Stephen Boyd <sboyd@codeaurora.org> Reported-by:
Lime Yang <limey@codeaurora.org> Signed-off-by:
Vikram Mulukutla <markivx@codeaurora.org> Signed-off-by:
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Konstantin Khlebnikov authored
commit 69abaffe upstream. Cfq_lookup_create_cfqg() allocates struct blkcg_gq using GFP_ATOMIC. In cfq_find_alloc_queue() possible allocation failure is not handled. As a result kernel oopses on NULL pointer dereference when cfq_link_cfqq_cfqg() calls cfqg_get() for NULL pointer. Bug was introduced in v3.5 in commit cd1604fa ("blkcg: factor out blkio_group creation"). Prior to that commit cfq group lookup had returned pointer to root group as fallback. This patch handles this error using existing fallback oom_cfqq. Signed-off-by:
Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Acked-by:
Tejun Heo <tj@kernel.org> Acked-by:
Vivek Goyal <vgoyal@redhat.com> Fixes: cd1604fa ("blkcg: factor out blkio_group creation") Signed-off-by:
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Shobhit Kumar authored
commit d180d2bb upstream. As per the specififcation, the SB_DevFn is the PCI_DEVFN of the target device and not the source. So PCI_DEVFN(2,0) is not correct. Further the port ID should be enough to identify devices unless they are MFD. The SB_DevFn was intended to remove ambiguity in case of these MFD devices. For non MFD devices the recommendation for the target device IP was to ignore these fields, but not all of them followed the recommendation. Some like CCK ignore these fields and hence PCI_DEVFN(2, 0) works and so does PCI_DEVFN(0, 0) as it works for DPIO. The issue came to light because of GPIONC which was not getting programmed correctly with PCI_DEVFN(2, 0). It turned out that this did not follow the recommendation and expected 0 in this field. In general the recommendation is to use SB_DevFn as PCI_DEVFN(0, 0) for all devices except target PCI devices. Signed-off-by:
Shobhit Kumar <shobhit.kumar@intel.com> Reviewed-by:
Ville Syrjälä <ville.syrjala@linux.intel.com> Signed-off-by:
Jani Nikula <jani.nikula@intel.com> Signed-off-by:
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David Hildenbrand authored
commit 8e2207cd upstream. If a vm with no VCPUs is created, the injection of a floating irq leads to an endless loop in the kernel. Let's skip the search for a destination VCPU for a floating irq if no VCPUs were created. Reviewed-by:
Dominik Dingel <dingel@linux.vnet.ibm.com> Reviewed-by:
Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by:
David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by:
Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by:
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Hans de Goede authored
commit e77a1635 upstream. Backlight control through the native intel interface does not work properly on the Samsung 510R, where as using the acpi_video interface does work, add a quirk for this. Link: https://bugzilla.redhat.com/show_bug.cgi?id=1186097Signed-off-by:
Hans de Goede <hdegoede@redhat.com> Signed-off-by:
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Hans de Goede authored
commit 3295d730 upstream. The Samsung 730U3E/740U3E has integrated ATI Radeon graphics, and backlight control does not work properly when using the native interfaces. Link: https://bugzilla.redhat.com/show_bug.cgi?id=1094948Signed-off-by:
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Hans de Goede authored
commit 6a3ef10b upstream. The L521X variant of the Dell XPS15 has integrated nvidia graphics, and backlight control does not work properly when using the native interfaces. Link: https://bugzilla.redhat.com/show_bug.cgi?id=1163574Signed-off-by:
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Aaron Lu authored
commit 7d0b9349 upstream. Several Samsung laptop models (SAMSUNG 870Z5E/880Z5E/680Z5E and SAMSUNG 370R4E/370R4V/370R5E/3570RE/370R5V) do not have a working native backlight control interface so restore their acpi_videoX interface. Link: https://bugzilla.kernel.org/show_bug.cgi?id=84221 Link: https://bugzilla.kernel.org/show_bug.cgi?id=84651 For SAMSUNG 870Z5E/880Z5E/680Z5E: Reported-and-tested-by:
Brent Saner <brent.saner@gmail.com> Reported-by:
Vitaliy Filippov <vitalif@yourcmc.ru> Reported-by:
Laszlo KREKACS <laszlo.krekacs.list@gmail.com> For SAMSUNG 370R4E/370R4V/370R5E/3570RE/370R5V: Reported-by:
Vladimir Perepechin <vovochka13@gmail.com> Signed-off-by:
Aaron Lu <aaron.lu@intel.com> Signed-off-by:
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Ross Lagerwall authored
commit 72978b2f upstream. Commit 61a734d3 ("xen/manage: Always freeze/thaw processes when suspend/resuming") ensured that userspace processes were always frozen before suspending to reduce interaction issues when resuming devices. However, freeze_processes() does not freeze kernel threads. Freeze kernel threads as well to prevent deadlocks with the khubd thread when resuming devices. This is what native suspend and resume does. Example deadlock: [ 7279.648010] [<ffffffff81446bde>] ? xen_poll_irq_timeout+0x3e/0x50 [ 7279.648010] [<ffffffff81448d60>] xen_poll_irq+0x10/0x20 [ 7279.648010] [<ffffffff81011723>] xen_lock_spinning+0xb3/0x120 [ 7279.648010] [<ffffffff810115d1>] __raw_callee_save_xen_lock_spinning+0x11/0x20 [ 7279.648010] [<ffffffff815620b6>] ? usb_control_msg+0xe6/0x120 [ 7279.648010] [<ffffffff81747e50>] ? _raw_spin_lock_irq+0x50/0x60 [ 7279.648010] [<ffffffff8174522c>] wait_for_completion+0xac/0x160 [ 7279.648010] [<ffffffff8109c520>] ? try_to_wake_up+0x2c0/0x2c0 [ 7279.648010] [<ffffffff814b60f2>] dpm_wait+0x32/0x40 [ 7279.648010] [<ffffffff814b6eb0>] device_resume+0x90/0x210 [ 7279.648010] [<ffffffff814b7d71>] dpm_resume+0x121/0x250 [ 7279.648010] [<ffffffff8144c570>] ? xenbus_dev_request_and_reply+0xc0/0xc0 [ 7279.648010] [<ffffffff814b80d5>] dpm_resume_end+0x15/0x30 [ 7279.648010] [<ffffffff81449fba>] do_suspend+0x10a/0x200 [ 7279.648010] [<ffffffff8144a2f0>] ? xen_pre_suspend+0x20/0x20 [ 7279.648010] [<ffffffff8144a1d0>] shutdown_handler+0x120/0x150 [ 7279.648010] [<ffffffff8144c60f>] xenwatch_thread+0x9f/0x160 [ 7279.648010] [<ffffffff810ac510>] ? finish_wait+0x80/0x80 [ 7279.648010] [<ffffffff8108d189>] kthread+0xc9/0xe0 [ 7279.648010] [<ffffffff8108d0c0>] ? flush_kthread_worker+0x80/0x80 [ 7279.648010] [<ffffffff8175087c>] ret_from_fork+0x7c/0xb0 [ 7279.648010] [<ffffffff8108d0c0>] ? flush_kthread_worker+0x80/0x80 [ 7441.216287] INFO: task khubd:89 blocked for more than 120 seconds. [ 7441.219457] Tainted: G X 3.13.11-ckt12.kz #1 [ 7441.222176] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 7441.225827] khubd D ffff88003f433440 0 89 2 0x00000000 [ 7441.229258] ffff88003ceb9b98 0000000000000046 ffff88003ce83000 0000000000013440 [ 7441.232959] ffff88003ceb9fd8 0000000000013440 ffff88003cd13000 ffff88003ce83000 [ 7441.236658] 0000000000000286 ffff88003d3e0000 ffff88003ceb9bd0 00000001001aa01e [ 7441.240415] Call Trace: [ 7441.241614] [<ffffffff817442f9>] schedule+0x29/0x70 [ 7441.243930] [<ffffffff81743406>] schedule_timeout+0x166/0x2c0 [ 7441.246681] [<ffffffff81075b80>] ? call_timer_fn+0x110/0x110 [ 7441.249339] [<ffffffff8174357e>] schedule_timeout_uninterruptible+0x1e/0x20 [ 7441.252644] [<ffffffff81077710>] msleep+0x20/0x30 [ 7441.254812] [<ffffffff81555f00>] hub_port_reset+0xf0/0x580 [ 7441.257400] [<ffffffff81558465>] hub_port_init+0x75/0xb40 [ 7441.259981] [<ffffffff814bb3c9>] ? update_autosuspend+0x39/0x60 [ 7441.262817] [<ffffffff814bb4f0>] ? pm_runtime_set_autosuspend_delay+0x50/0xa0 [ 7441.266212] [<ffffffff8155a64a>] hub_thread+0x71a/0x1750 [ 7441.268728] [<ffffffff810ac510>] ? finish_wait+0x80/0x80 [ 7441.271272] [<ffffffff81559f30>] ? usb_port_resume+0x670/0x670 [ 7441.274067] [<ffffffff8108d189>] kthread+0xc9/0xe0 [ 7441.276305] [<ffffffff8108d0c0>] ? flush_kthread_worker+0x80/0x80 [ 7441.279131] [<ffffffff8175087c>] ret_from_fork+0x7c/0xb0 [ 7441.281659] [<ffffffff8108d0c0>] ? flush_kthread_worker+0x80/0x80 Signed-off-by:
Ross Lagerwall <ross.lagerwall@citrix.com> Signed-off-by:
David Vrabel <david.vrabel@citrix.com> Signed-off-by:
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Takashi Iwai authored
commit 4227de2a upstream. Toshiba Satellite S50D laptop with an IDT codec uses the GPIO4 (0x10) as the master EAPD. Bugzilla: https://bugzilla.novell.com/show_bug.cgi?id=915858Signed-off-by:
Takashi Iwai <tiwai@suse.de> Signed-off-by:
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Takashi Iwai authored
commit 8695a003 upstream. NID 0x10 seems corresponding to the bass speaker. Signed-off-by:
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James Hogan authored
commit f798217d upstream. The FPU and DSP are enabled via the CP0 Status CU1 and MX bits by kvm_mips_set_c0_status() on a guest exit, presumably in case there is active state that needs saving if pre-emption occurs. However neither of these bits are cleared again when returning to the guest. This effectively gives the guest access to the FPU/DSP hardware after the first guest exit even though it is not aware of its presence, allowing FP instructions in guest user code to intermittently actually execute instead of trapping into the guest OS for emulation. It will then read & manipulate the hardware FP registers which technically belong to the user process (e.g. QEMU), or are stale from another user process. It can also crash the guest OS by causing an FP exception, for which a guest exception handler won't have been registered. First lets save and disable the FPU (and MSA) state with lose_fpu(1) before entering the guest. This simplifies the problem, especially for when guest FPU/MSA support is added in the future, and prevents FR=1 FPU state being live when the FR bit gets cleared for the guest, which according to the architecture causes the contents of the FPU and vector registers to become UNPREDICTABLE. We can then safely remove the enabling of the FPU in kvm_mips_set_c0_status(), since there should never be any active FPU or MSA state to save at pre-emption, which should plug the FPU leak. DSP state is always live rather than being lazily restored, so for that it is simpler to just clear the MX bit again when re-entering the guest. Signed-off-by:
James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Sanjay Lal <sanjayl@kymasys.com> Cc: Gleb Natapov <gleb@kernel.org> Cc: kvm@vger.kernel.org Cc: linux-mips@linux-mips.org Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com> [ luis: backported to 3.16: files rename: - locore.S -> kvm_locore.S - mips.c -> kvm_mips.c ] Signed-off-by:
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Alexander Usyskin authored
commit 663b7ee9 upstream. We might enter the interrupt handler with hw_ready already set, but prior we actually started the reset flow. To soleve this we move the reset release from the interrupt handler to the HW start wait function which is part of the reset sequence. Signed-off-by:
Alexander Usyskin <alexander.usyskin@intel.com> Signed-off-by:
Tomas Winkler <tomas.winkler@intel.com> Signed-off-by:
Greg Kroah-Hartman <gregkh@linuxfoundation.org> [ luis: backported to 3.16: adjusted context ] Signed-off-by:
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Alexander Usyskin authored
commit 1ab1e79b upstream. We should mask interrupt set bit when writing back hcsr value in reset bit clean-up. This is refinement for mei: clean reset bit before reset commit b13a65efSigned-off-by:
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Malcolm Priestley authored
commit 15e1ce33 upstream. A quirk of some older firmwares that report endpoint pipe type as PIPE_BULK but the endpoint otheriwse functions as interrupt. Check if usb_endpoint_type is USB_ENDPOINT_XFER_BULK and set as usb_rcvbulkpipe. Signed-off-by:
Malcolm Priestley <tvboxspy@gmail.com> Signed-off-by:
Mauro Carvalho Chehab <mchehab@osg.samsung.com> Signed-off-by:
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Peng Tao authored
commit cb5d04bc upstream. With pgio refactoring in v3.15, .init_read and .init_write can be called with valid pgio->pg_lseg. file layout was fixed at that time by commit c6194271 (pnfs: filelayout: support non page aligned layouts). But the generic helper still needs to be fixed. Signed-off-by:
Peng Tao <tao.peng@primarydata.com> Signed-off-by:
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Matej Dubovy authored
commit 8f0c304c upstream. Please add support for sub BT chip on the combo card Broadcom 43142A0 (in Lenovo E145), 04ca:2007 /sys/kernel/debug/usb/devices T: Bus=05 Lev=01 Prnt=01 Port=01 Cnt=02 Dev#= 3 Spd=12 MxCh= 0 D: Ver= 2.00 Cls=ff(vend.) Sub=01 Prot=01 MxPS=64 #Cfgs= 1 P: Vendor=04ca ProdID=2007 Rev= 1.12 S: Manufacturer=Broadcom Corp S: Product=BCM43142A0 S: SerialNumber=28E347EC73BD C:* #Ifs= 4 Cfg#= 1 Atr=e0 MxPwr= 0mA I:* If#= 0 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=01 Prot=01 Driver=(none) E: Ad=81(I) Atr=03(Int.) MxPS= 16 Ivl=1ms E: Ad=82(I) Atr=02(Bulk) MxPS= 64 Ivl=0ms E: Ad=02(O) Atr=02(Bulk) MxPS= 64 Ivl=0ms I:* If#= 1 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=01 Prot=01 Driver=(none) E: Ad=83(I) Atr=01(Isoc) MxPS= 0 Ivl=1ms E: Ad=03(O) Atr=01(Isoc) MxPS= 0 Ivl=1ms I: If#= 1 Alt= 1 #EPs= 2 Cls=ff(vend.) Sub=01 Prot=01 Driver=(none) E: Ad=83(I) Atr=01(Isoc) MxPS= 9 Ivl=1ms E: Ad=03(O) Atr=01(Isoc) MxPS= 9 Ivl=1ms I: If#= 1 Alt= 2 #EPs= 2 Cls=ff(vend.) Sub=01 Prot=01 Driver=(none) E: Ad=83(I) Atr=01(Isoc) MxPS= 17 Ivl=1ms E: Ad=03(O) Atr=01(Isoc) MxPS= 17 Ivl=1ms I: If#= 1 Alt= 3 #EPs= 2 Cls=ff(vend.) Sub=01 Prot=01 Driver=(none) E: Ad=83(I) Atr=01(Isoc) MxPS= 25 Ivl=1ms E: Ad=03(O) Atr=01(Isoc) MxPS= 25 Ivl=1ms I: If#= 1 Alt= 4 #EPs= 2 Cls=ff(vend.) Sub=01 Prot=01 Driver=(none) E: Ad=83(I) Atr=01(Isoc) MxPS= 33 Ivl=1ms E: Ad=03(O) Atr=01(Isoc) MxPS= 33 Ivl=1ms I: If#= 1 Alt= 5 #EPs= 2 Cls=ff(vend.) Sub=01 Prot=01 Driver=(none) E: Ad=83(I) Atr=01(Isoc) MxPS= 49 Ivl=1ms E: Ad=03(O) Atr=01(Isoc) MxPS= 49 Ivl=1ms I:* If#= 2 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=ff Prot=ff Driver=(none) E: Ad=84(I) Atr=02(Bulk) MxPS= 32 Ivl=0ms E: Ad=04(O) Atr=02(Bulk) MxPS= 32 Ivl=0ms I:* If#= 3 Alt= 0 #EPs= 0 Cls=fe(app. ) Sub=01 Prot=01 Driver=(none) Firmware for 04ca:2007 can be extracted from the latest Lenovo E145 Bluetooth driver for Windows (driver is however described as BCM20702 but contains also firwmare for BCM43142). Search for BCM43142A0_001.001.011.0122.0153.hex within hex files, then it must be converted using hex2hcd utility. Rename file to BCM43142A0-04ca-2007.hcd, then move to /lib/firmware/brcm/. Signed-off-by:
Matej Dubovy <matej.dubovy@gmail.com> Signed-off-by:
Marcel Holtmann <marcel@holtmann.org> Signed-off-by:
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Viresh Kumar authored
commit 6ffae8c0 upstream. In __cpufreq_remove_dev_finish(), per-cpu 'cpufreq_cpu_data' needs to be cleared before calling kobject_put(&policy->kobj) and under cpufreq_driver_lock. Otherwise, if someone else calls cpufreq_cpu_get() in parallel with it, they can obtain a non-NULL policy from that after kobject_put(&policy->kobj) was executed. Consider this case: Thread A Thread B cpufreq_cpu_get() acquire cpufreq_driver_lock read-per-cpu cpufreq_cpu_data kobject_put(&policy->kobj); kobject_get(&policy->kobj); ... per_cpu(&cpufreq_cpu_data, cpu) = NULL And this will result in a warning like this one: ------------[ cut here ]------------ WARNING: CPU: 0 PID: 4 at include/linux/kref.h:47 kobject_get+0x41/0x50() Modules linked in: acpi_cpufreq(+) nfsd auth_rpcgss nfs_acl lockd grace sunrpc xfs libcrc32c sd_mod ixgbe igb mdio ahci hwmon ... Call Trace: [<ffffffff81661b14>] dump_stack+0x46/0x58 [<ffffffff81072b61>] warn_slowpath_common+0x81/0xa0 [<ffffffff81072c7a>] warn_slowpath_null+0x1a/0x20 [<ffffffff812e16d1>] kobject_get+0x41/0x50 [<ffffffff815262a5>] cpufreq_cpu_get+0x75/0xc0 [<ffffffff81527c3e>] cpufreq_update_policy+0x2e/0x1f0 [<ffffffff810b8cb2>] ? up+0x32/0x50 [<ffffffff81381aa9>] ? acpi_ns_get_node+0xcb/0xf2 [<ffffffff81381efd>] ? acpi_evaluate_object+0x22c/0x252 [<ffffffff813824f6>] ? acpi_get_handle+0x95/0xc0 [<ffffffff81360967>] ? acpi_has_method+0x25/0x40 [<ffffffff81391e08>] acpi_processor_ppc_has_changed+0x77/0x82 [<ffffffff81089566>] ? move_linked_works+0x66/0x90 [<ffffffff8138e8ed>] acpi_processor_notify+0x58/0xe7 [<ffffffff8137410c>] acpi_ev_notify_dispatch+0x44/0x5c [<ffffffff8135f293>] acpi_os_execute_deferred+0x15/0x22 [<ffffffff8108c910>] process_one_work+0x160/0x410 [<ffffffff8108d05b>] worker_thread+0x11b/0x520 [<ffffffff8108cf40>] ? rescuer_thread+0x380/0x380 [<ffffffff81092421>] kthread+0xe1/0x100 [<ffffffff81092340>] ? kthread_create_on_node+0x1b0/0x1b0 [<ffffffff81669ebc>] ret_from_fork+0x7c/0xb0 [<ffffffff81092340>] ? kthread_create_on_node+0x1b0/0x1b0 ---[ end trace 89e66eb9795efdf7 ]--- The actual code flow is as follows: Thread A: Workqueue: kacpi_notify acpi_processor_notify() acpi_processor_ppc_has_changed() cpufreq_update_policy() cpufreq_cpu_get() kobject_get() Thread B: xenbus_thread() xenbus_thread() msg->u.watch.handle->callback() handle_vcpu_hotplug_event() vcpu_hotplug() cpu_down() __cpu_notify(CPU_POST_DEAD..) cpufreq_cpu_callback() __cpufreq_remove_dev_finish() cpufreq_policy_put_kobj() kobject_put() cpufreq_cpu_get() gets the policy from per-cpu variable cpufreq_cpu_data under cpufreq_driver_lock, and once it gets a valid policy it expects it to not be freed until cpufreq_cpu_put() is called. But the race happens when another thread puts the kobject first and updates cpufreq_cpu_data before or later. And so the first thread gets a valid policy structure and before it does kobject_get() on it, the second one has already done kobject_put(). Fix this by setting cpufreq_cpu_data to NULL before putting the kobject and that too under locks. Reported-by:
Ethan Zhao <ethan.zhao@oracle.com> Reported-by:
Santosh Shilimkar <santosh.shilimkar@oracle.com> Signed-off-by:
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Stefan Agner authored
commit 5f1437f6 upstream. When the UART is in DMA receive mode (RDMAS set) and one character just arrived while another interrupt is handled (e.g. TX), the RDRF (receiver data register full flag) is set due to the water level of 1. But since the DMA will take care of this character, there is no need to handle it by calling lpuart_prepare_rx. Handling it leads to adding the RX timeout timer twice: [ 74.336698] Kernel BUG at 80053070 [verbose debug info unavailable] [ 74.342999] Internal error: Oops - BUG: 0 [#1] ARM0:00.00 khungtaskd [ 74.347817] Modules linked in: 0 S 0.0 0.0 0:00.00 writeback [ 74.350926] CPU: 0 PID: 0 Comm: swapper Not tainted 3.19.0-rc3-00001-g39d78e2 #1788 [ 74.358617] Hardware name: Freescale Vybrid VF610 (Device Tree)t [ 74.364563] task: 807a7678 ti: 8079c000 task.ti: 8079c000 kblockd [ 74.370002] PC is at add_timer+0x24/0x28.0 0.0 0:00.09 kworker/u2:1 [ 74.373960] LR is at lpuart_int+0x15c/0x3d8 [ 74.378171] pc : [<80053070>] lr : [<802e0d88>] psr: a0010193 [ 74.378171] sp : 8079de10 ip : 8079de20 fp : 8079de1c [ 74.389694] r10: 807d44c0 r9 : 8688c300 r8 : 00000013 [ 74.394943] r7 : 20010193 r6 : 00000000 r5 : 000000a0 r4 : 86997210 [ 74.401498] r3 : ffffa7da r2 : 80817868 r1 : 86997210 r0 : 86997344 [ 74.408052] Flags: NzCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment kernel [ 74.415489] Control: 10c5387d Table: 8611c059 DAC: 00000015 [ 74.421265] Process swapper (pid: 0, stack limit = 0x8079c230) ... Solve this by only execute the receiver path (lpuart_prepare_rx) if the DMA receive mode (RDMAS) is not set. Also, make sure the flag is cleared on initialization, in case it has been left set. This can be best reproduced using UART as a serial console, then running top while dd'ing data into the terminal. Signed-off-by:
Stefan Agner <stefan@agner.ch> Signed-off-by:
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Stefan Agner authored
commit 4a8588a1 upstream. If the serial port gets closed while a RX transfer is in progress, the timer might fire after the serial port shutdown finished. This leads in a NULL pointer dereference: [ 7.508324] Unable to handle kernel NULL pointer dereference at virtual address 00000000 [ 7.516590] pgd = 86348000 [ 7.519445] [00000000] *pgd=86179831, *pte=00000000, *ppte=00000000 [ 7.526145] Internal error: Oops: 17 [#1] ARM [ 7.530611] Modules linked in: [ 7.533876] CPU: 0 PID: 123 Comm: systemd Not tainted 3.19.0-rc3-00004-g5b11ea7 #1778 [ 7.541827] Hardware name: Freescale Vybrid VF610 (Device Tree) [ 7.547862] task: 861c3400 ti: 86ac8000 task.ti: 86ac8000 [ 7.553392] PC is at lpuart_timer_func+0x24/0xf8 [ 7.558127] LR is at lpuart_timer_func+0x20/0xf8 [ 7.562857] pc : [<802df99c>] lr : [<802df998>] psr: 600b0113 [ 7.562857] sp : 86ac9b90 ip : 86ac9b90 fp : 86ac9bbc [ 7.574467] r10: 80817180 r9 : 80817b98 r8 : 80817998 [ 7.579803] r7 : 807acee0 r6 : 86989000 r5 : 00000100 r4 : 86997210 [ 7.586444] r3 : 86ac8000 r2 : 86ac9bc0 r1 : 86997210 r0 : 00000000 [ 7.593085] Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user [ 7.600341] Control: 10c5387d Table: 86348059 DAC: 00000015 [ 7.606203] Process systemd (pid: 123, stack limit = 0x86ac8230) Setup the timer on UART startup which allows to delete the timer unconditionally on shutdown. This also saves the initialization on each transfer. Signed-off-by:
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Peter Hurley authored
commit 37480a05 upstream. Commit 26df6d13 ("tty: Add EXTPROC support for LINEMODE") allows a process which has opened a pty master to send _any_ signal to the process group of the pty slave. Although potentially exploitable by a malicious program running a setuid program on a pty slave, it's unknown if this exploit currently exists. Limit to signals actually used. Cc: Theodore Ts'o <tytso@mit.edu> Cc: Howard Chu <hyc@symas.com> Cc: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk> Cc: Jiri Slaby <jslaby@suse.cz> Signed-off-by:
Peter Hurley <peter@hurleysoftware.com> Signed-off-by:
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Nicolas Pitre authored
commit 19e3ae6b upstream. The vcs device's poll/fasync support relies on the vt notifier to signal changes to the screen content. Notifier invocations were missing for changes that comes through the selection interface though. Fix that. Tested with BRLTTY 5.2. Signed-off-by:
Nicolas Pitre <nico@linaro.org> Cc: Dave Mielke <dave@mielke.cc> Signed-off-by:
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Luciano Coelho authored
commit fd66fc1c upstream. When iwl_mvm_power_update_mac() is called, we have already added the mac context, so if this call fails we should remove the mac. Fixes: commit e5e7aa8e ('iwlwifi: mvm: refactor power code') Signed-off-by:
Luciano Coelho <luciano.coelho@intel.com> Reviewed-by:
Johannes Berg <johannes.berg@intel.com> Signed-off-by:
Emmanuel Grumbach <emmanuel.grumbach@intel.com> Signed-off-by:
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Emmanuel Grumbach authored
commit cd8f4384 upstream. The base address of the scheduler in the device's memory (SRAM) comes from two different sources. The periphery register and the alive notification from the firmware. We have a check in iwl_pcie_tx_start that ensures that they are the same. When we resume from WoWLAN, the firmware may have crashed for whatever reason. In that case, the whole device may be reset which means that the periphery register will hold a meaningless value. When we come to compare trans_pcie->scd_base_addr (which really holds the value we had when we loaded the WoWLAN firmware upon suspend) and the current value of the register, we don't see a match unsurprisingly. Trick the check to avoid a loud yet harmless WARN. Note that when the WoWLAN has crashed, we will see that in iwl_trans_pcie_d3_resume which will let the op_mode know. Once the op_mode is informed that the WowLAN firmware has crashed, it can't do much besides resetting the whole device. Reviewed-by:
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Luciano Coelho authored
commit 5523d11c upstream. We don't really need to use different mac colors when adding mac contexts, because they're not used anywhere. In fact, the firmware doesn't accept 255 as a valid color, so we get into a SYSASSERT 0x3401 when we reach that. Remove the color increment to use always zero and avoid reaching 255. Signed-off-by:
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Alan Stern authored
commit c9919790 upstream. The usb_hcd_unlink_urb() routine in hcd.c contains two possible use-after-free errors. The dev_dbg() statement at the end of the routine dereferences urb and urb->dev even though both structures may have been deallocated. This patch fixes the problem by storing urb->dev in a local variable (avoiding the dereference of urb) and moving the dev_dbg() up before the usb_put_dev() call. Signed-off-by:
Alan Stern <stern@rowland.harvard.edu> Reported-by:
Joe Lawrence <joe.lawrence@stratus.com> Tested-by:
Greg Kroah-Hartman <greg@kroah.com> Signed-off-by:
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Alan Stern authored
commit 074f9dd5 upstream. Currently the USB stack assumes that all host controller drivers are capable of receiving wakeup requests from downstream devices. However, this isn't true for the isp1760-hcd driver, which means that it isn't safe to do a runtime suspend of any device attached to a root-hub port if the device requires wakeup. This patch adds a "cant_recv_wakeups" flag to the usb_hcd structure and sets the flag in isp1760-hcd. The core is modified to prevent a direct child of the root hub from being put into runtime suspend with wakeup enabled if the flag is set. Signed-off-by:
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