- 26 Jun, 2020 20 commits
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Muchun Song authored
We should put the css reference when memory allocation failed. Link: http://lkml.kernel.org/r/20200614122653.98829-1-songmuchun@bytedance.com Fixes: f0a3a24b ("mm: memcg/slab: rework non-root kmem_cache lifecycle management") Signed-off-by: Muchun Song <songmuchun@bytedance.com> Acked-by: Roman Gushchin <guro@fb.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: Qian Cai <cai@lca.pw> 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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Johannes Weiner authored
Tejun reports seeing rare div0 crashes in memory.low stress testing: RIP: 0010:mem_cgroup_calculate_protection+0xed/0x150 Code: 0f 46 d1 4c 39 d8 72 57 f6 05 16 d6 42 01 40 74 1f 4c 39 d8 76 1a 4c 39 d1 76 15 4c 29 d1 4c 29 d8 4d 29 d9 31 d2 48 0f af c1 <49> f7 f1 49 01 c2 4c 89 96 38 01 00 00 5d c3 48 0f af c7 31 d2 49 RSP: 0018:ffffa14e01d6fcd0 EFLAGS: 00010246 RAX: 000000000243e384 RBX: 0000000000000000 RCX: 0000000000008f4b RDX: 0000000000000000 RSI: ffff8b89bee84000 RDI: 0000000000000000 RBP: ffffa14e01d6fcd0 R08: ffff8b89ca7d40f8 R09: 0000000000000000 R10: 0000000000000000 R11: 00000000006422f7 R12: 0000000000000000 R13: ffff8b89d9617000 R14: ffff8b89bee84000 R15: ffffa14e01d6fdb8 FS: 0000000000000000(0000) GS:ffff8b8a1f1c0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f93b1fc175b CR3: 000000016100a000 CR4: 0000000000340ea0 Call Trace: shrink_node+0x1e5/0x6c0 balance_pgdat+0x32d/0x5f0 kswapd+0x1d7/0x3d0 kthread+0x11c/0x160 ret_from_fork+0x1f/0x30 This happens when parent_usage == siblings_protected. We check that usage is bigger than protected, which should imply parent_usage being bigger than siblings_protected. However, we don't read (or even update) these values atomically, and they can be out of sync as the memory state changes under us. A bit of fluctuation around the target protection isn't a big deal, but we need to handle the div0 case. Check the parent state explicitly to make sure we have a reasonable positive value for the divisor. Link: http://lkml.kernel.org/r/20200615140658.601684-1-hannes@cmpxchg.org Fixes: 8a931f80 ("mm: memcontrol: recursive memory.low protection") Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Reported-by: Tejun Heo <tj@kernel.org> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Chris Down <chris@chrisdown.name> Cc: Roman Gushchin <guro@fb.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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Masanari Iida authored
This patch fixes following warning while "make xmldocs" mm/vmalloc.c:1877: warning: Excess function parameter 'prot' description in 'vm_map_ram' This warning started since commit d4efd79a ("mm: remove the prot argument from vm_map_ram"). Link: http://lkml.kernel.org/r/20200622152850.140871-1-standby24x7@gmail.com Fixes: d4efd79a ("mm: remove the prot argument from vm_map_ram") Signed-off-by: Masanari Iida <standby24x7@gmail.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Nathan Chancellor authored
After mm.h was removed from the asm-generic version of cacheflush.h, s390 allyesconfig shows several warnings of the following nature: In file included from arch/s390/include/generated/asm/cacheflush.h:1, from drivers/media/platform/omap3isp/isp.c:42: include/asm-generic/cacheflush.h:16:42: warning: 'struct mm_struct' declared inside parameter list will not be visible outside of this definition or declaration As Geert and Laurent point out, this driver does not need this header in the two files that include it. Remove it so there are no warnings. Link: http://lkml.kernel.org/r/20200622234740.72825-2-natechancellor@gmail.com Fixes: e0cf615d ("asm-generic: don't include <linux/mm.h> in cacheflush.h") Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Suggested-by: Geert Uytterhoeven <geert@linux-m68k.org> Suggested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Stephen Rothwell authored
Some s390 builds get these warnings: include/asm-generic/cacheflush.h:16:42: warning: 'struct mm_struct' declared inside parameter list will not be visible outside of this definition or declaration include/asm-generic/cacheflush.h:22:46: warning: 'struct mm_struct' declared inside parameter list will not be visible outside of this definition or declaration include/asm-generic/cacheflush.h:28:45: warning: 'struct vm_area_struct' declared inside parameter list will not be visible outside of this definition or declaration include/asm-generic/cacheflush.h:36:44: warning: 'struct vm_area_struct' declared inside parameter list will not be visible outside of this definition or declaration include/asm-generic/cacheflush.h:44:45: warning: 'struct page' declared inside parameter list will not be visible outside of this definition or declaration include/asm-generic/cacheflush.h:52:50: warning: 'struct address_space' declared inside parameter list will not be visible outside of this definition or declaration include/asm-generic/cacheflush.h:58:52: warning: 'struct address_space' declared inside parameter list will not be visible outside of this definition or declaration include/asm-generic/cacheflush.h:75:17: warning: 'struct page' declared inside parameter list will not be visible outside of this definition or declaration include/asm-generic/cacheflush.h:74:45: warning: 'struct vm_area_struct' declared inside parameter list will not be visible outside of this definition or declaration include/asm-generic/cacheflush.h:82:16: warning: 'struct page' declared inside parameter list will not be visible outside of this definition or declaration include/asm-generic/cacheflush.h:81:50: warning: 'struct vm_area_struct' declared inside parameter list will not be visible outside of this definition or declaration Forward declare the named structs to get rid of these. Link: http://lkml.kernel.org/r/20200623135714.4dae4b8a@canb.auug.org.au Fixes: e0cf615d ("asm-generic: don't include <linux/mm.h> in cacheflush.h") Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Arnd Bergmann <arnd@arndb.de> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Christophe Leroy authored
Since commit 9e343b46 ("READ_ONCE: Enforce atomicity for {READ,WRITE}_ONCE() memory accesses"), READ_ONCE() cannot be used anymore to read complex page table entries. This leads to: CC mm/debug_vm_pgtable.o In file included from ./include/asm-generic/bug.h:5, from ./arch/powerpc/include/asm/bug.h:109, from ./include/linux/bug.h:5, from ./include/linux/mmdebug.h:5, from ./include/linux/gfp.h:5, from mm/debug_vm_pgtable.c:13: In function 'pte_clear_tests', inlined from 'debug_vm_pgtable' at mm/debug_vm_pgtable.c:363:2: ./include/linux/compiler.h:392:38: error: Unsupported access size for {READ,WRITE}_ONCE(). mm/debug_vm_pgtable.c:249:14: note: in expansion of macro 'READ_ONCE' 249 | pte_t pte = READ_ONCE(*ptep); | ^~~~~~~~~ make[2]: *** [mm/debug_vm_pgtable.o] Error 1 Fix it by using the recently added ptep_get() helper. Link: http://lkml.kernel.org/r/6ca8c972e6c920dc4ae0d4affbed9703afa4d010.1592490570.git.christophe.leroy@csgroup.eu Fixes: 9e343b46 ("READ_ONCE: Enforce atomicity for {READ,WRITE}_ONCE() memory accesses") Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Acked-by: Will Deacon <will@kernel.org> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Arjun Roy authored
Calls to pte_offset_map() in vm_insert_pages() are erroneously not matched with a call to pte_unmap(). This would cause problems on architectures where that is not a no-op. This patch does away with the non-traditional locking in the existing code, and instead uses pte_offset_map_lock/unlock() as usual, incrementing PTE as necessary. The PTE pointer is kept within bounds since we clamp it with PTRS_PER_PTE. Link: http://lkml.kernel.org/r/20200618220446.20284-1-arjunroy.kdev@gmail.com Fixes: 8cd3984d ("mm/memory.c: add vm_insert_pages()") Signed-off-by: Arjun Roy <arjunroy@google.com> Acked-by: David Rientjes <rientjes@google.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Hugh Dickins authored
Chris Murphy reports that a slightly overcommitted load, testing swap and zram along with i915, splats and keeps on splatting, when it had better fail less noisily: gnome-shell: page allocation failure: order:0, mode:0x400d0(__GFP_IO|__GFP_FS|__GFP_COMP|__GFP_RECLAIMABLE), nodemask=(null),cpuset=/,mems_allowed=0 CPU: 2 PID: 1155 Comm: gnome-shell Not tainted 5.7.0-1.fc33.x86_64 #1 Call Trace: dump_stack+0x64/0x88 warn_alloc.cold+0x75/0xd9 __alloc_pages_slowpath.constprop.0+0xcfa/0xd30 __alloc_pages_nodemask+0x2df/0x320 alloc_slab_page+0x195/0x310 allocate_slab+0x3c5/0x440 ___slab_alloc+0x40c/0x5f0 __slab_alloc+0x1c/0x30 kmem_cache_alloc+0x20e/0x220 xas_nomem+0x28/0x70 add_to_swap_cache+0x321/0x400 __read_swap_cache_async+0x105/0x240 swap_cluster_readahead+0x22c/0x2e0 shmem_swapin+0x8e/0xc0 shmem_swapin_page+0x196/0x740 shmem_getpage_gfp+0x3a2/0xa60 shmem_read_mapping_page_gfp+0x32/0x60 shmem_get_pages+0x155/0x5e0 [i915] __i915_gem_object_get_pages+0x68/0xa0 [i915] i915_vma_pin+0x3fe/0x6c0 [i915] eb_add_vma+0x10b/0x2c0 [i915] i915_gem_do_execbuffer+0x704/0x3430 [i915] i915_gem_execbuffer2_ioctl+0x1ea/0x3e0 [i915] drm_ioctl_kernel+0x86/0xd0 [drm] drm_ioctl+0x206/0x390 [drm] ksys_ioctl+0x82/0xc0 __x64_sys_ioctl+0x16/0x20 do_syscall_64+0x5b/0xf0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reported on 5.7, but it goes back really to 3.1: when shmem_read_mapping_page_gfp() was implemented for use by i915, and allowed for __GFP_NORETRY and __GFP_NOWARN flags in most places, but missed swapin's "& GFP_KERNEL" mask for page tree node allocation in __read_swap_cache_async() - that was to mask off HIGHUSER_MOVABLE bits from what page cache uses, but GFP_RECLAIM_MASK is now what's needed. Link: https://bugzilla.kernel.org/show_bug.cgi?id=208085 Link: http://lkml.kernel.org/r/alpine.LSU.2.11.2006151330070.11064@eggly.anvils Fixes: 68da9f05 ("tmpfs: pass gfp to shmem_getpage_gfp") Signed-off-by: Hugh Dickins <hughd@google.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reported-by: Chris Murphy <lists@colorremedies.com> Analyzed-by: Vlastimil Babka <vbabka@suse.cz> Analyzed-by: Matthew Wilcox <willy@infradead.org> Tested-by: Chris Murphy <lists@colorremedies.com> Cc: <stable@vger.kernel.org> [3.1+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Sebastian Andrzej Siewior authored
According to Christopher Lameter two fixes have been merged for the same problem. As far as I can tell, the code does not acquire the list_lock and invoke kmalloc(). list_slab_objects() misses an unlock (the counterpart to get_map()) and the memory allocated in free_partial() isn't used. Revert the mentioned commit. Link: http://lkml.kernel.org/r/20200618201234.795692-1-bigeasy@linutronix.de Fixes: aa456c7a ("slub: remove kmalloc under list_lock from list_slab_objects() V2") Link: https://lkml.kernel.org/r/alpine.DEB.2.22.394.2006181501480.12014@www.lameter.comSigned-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Yu Zhao <yuzhao@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Waiman Long authored
The kzfree() function is normally used to clear some sensitive information, like encryption keys, in the buffer before freeing it back to the pool. Memset() is currently used for buffer clearing. However unlikely, there is still a non-zero probability that the compiler may choose to optimize away the memory clearing especially if LTO is being used in the future. To make sure that this optimization will never happen, memzero_explicit(), which is introduced in v3.18, is now used in kzfree() to future-proof it. Link: http://lkml.kernel.org/r/20200616154311.12314-2-longman@redhat.com Fixes: 3ef0e5ba ("slab: introduce kzfree()") Signed-off-by: Waiman Long <longman@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: David Howells <dhowells@redhat.com> Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Cc: James Morris <jmorris@namei.org> Cc: "Serge E. Hallyn" <serge@hallyn.com> Cc: Joe Perches <joe@perches.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: David Rientjes <rientjes@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: "Jason A . Donenfeld" <Jason@zx2c4.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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Waiman Long authored
It was found that running the LTP test on a PowerPC system could produce erroneous values in /proc/meminfo, like: MemTotal: 531915072 kB MemFree: 507962176 kB MemAvailable: 1100020596352 kB Using bisection, the problem is tracked down to commit 9c315e4d ("mm: memcg/slab: cache page number in memcg_(un)charge_slab()"). In memcg_uncharge_slab() with a "int order" argument: unsigned int nr_pages = 1 << order; : mod_lruvec_state(lruvec, cache_vmstat_idx(s), -nr_pages); The mod_lruvec_state() function will eventually call the __mod_zone_page_state() which accepts a long argument. Depending on the compiler and how inlining is done, "-nr_pages" may be treated as a negative number or a very large positive number. Apparently, it was treated as a large positive number in that PowerPC system leading to incorrect stat counts. This problem hasn't been seen in x86-64 yet, perhaps the gcc compiler there has some slight difference in behavior. It is fixed by making nr_pages a signed value. For consistency, a similar change is applied to memcg_charge_slab() as well. Link: http://lkml.kernel.org/r/20200620184719.10994-1-longman@redhat.com Fixes: 9c315e4d ("mm: memcg/slab: cache page number in memcg_(un)charge_slab()"). Signed-off-by: Waiman Long <longman@redhat.com> Acked-by: Roman Gushchin <guro@fb.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.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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Randy Dunlap authored
Coccinelle scripts report the following errors: lib/test_hmm.c:523:20-26: ERROR: reference preceded by free on line 521 lib/test_hmm.c:524:21-27: ERROR: reference preceded by free on line 521 lib/test_hmm.c:523:28-35: ERROR: devmem is NULL but dereferenced. lib/test_hmm.c:524:29-36: ERROR: devmem is NULL but dereferenced. Fix these by using the local variable 'res' instead of devmem. Link: http://lkml.kernel.org/r/c845c158-9c65-9665-0d0b-00342846dd07@infradead.orgSigned-off-by: Randy Dunlap <rdunlap@infradead.org> Reviewed-by: Ralph Campbell <rcampbell@nvidia.com> Cc: Jérôme Glisse <jglisse@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Junxiao Bi authored
In the ocfs2 disk layout, slot number is 16 bits, but in ocfs2 implementation, slot number is 32 bits. Usually this will not cause any issue, because slot number is converted from u16 to u32, but OCFS2_INVALID_SLOT was defined as -1, when an invalid slot number from disk was obtained, its value was (u16)-1, and it was converted to u32. Then the following checking in get_local_system_inode will be always skipped: static struct inode **get_local_system_inode(struct ocfs2_super *osb, int type, u32 slot) { BUG_ON(slot == OCFS2_INVALID_SLOT); ... } Link: http://lkml.kernel.org/r/20200616183829.87211-5-junxiao.bi@oracle.comSigned-off-by: Junxiao Bi <junxiao.bi@oracle.com> Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com> Cc: Mark Fasheh <mark@fasheh.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Changwei Ge <gechangwei@live.cn> Cc: Gang He <ghe@suse.com> Cc: Jun Piao <piaojun@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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Junxiao Bi authored
The following kernel panic was captured when running nfs server over ocfs2, at that time ocfs2_test_inode_bit() was checking whether one inode locating at "blkno" 5 was valid, that is ocfs2 root inode, its "suballoc_slot" was OCFS2_INVALID_SLOT(65535) and it was allocted from //global_inode_alloc, but here it wrongly assumed that it was got from per slot inode alloctor which would cause array overflow and trigger kernel panic. BUG: unable to handle kernel paging request at 0000000000001088 IP: [<ffffffff816f6898>] _raw_spin_lock+0x18/0xf0 PGD 1e06ba067 PUD 1e9e7d067 PMD 0 Oops: 0002 [#1] SMP CPU: 6 PID: 24873 Comm: nfsd Not tainted 4.1.12-124.36.1.el6uek.x86_64 #2 Hardware name: Huawei CH121 V3/IT11SGCA1, BIOS 3.87 02/02/2018 RIP: _raw_spin_lock+0x18/0xf0 RSP: e02b:ffff88005ae97908 EFLAGS: 00010206 RAX: ffff88005ae98000 RBX: 0000000000001088 RCX: 0000000000000000 RDX: 0000000000020000 RSI: 0000000000000009 RDI: 0000000000001088 RBP: ffff88005ae97928 R08: 0000000000000000 R09: ffff880212878e00 R10: 0000000000007ff0 R11: 0000000000000000 R12: 0000000000001088 R13: ffff8800063c0aa8 R14: ffff8800650c27d0 R15: 000000000000ffff FS: 0000000000000000(0000) GS:ffff880218180000(0000) knlGS:ffff880218180000 CS: e033 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000001088 CR3: 00000002033d0000 CR4: 0000000000042660 Call Trace: igrab+0x1e/0x60 ocfs2_get_system_file_inode+0x63/0x3a0 [ocfs2] ocfs2_test_inode_bit+0x328/0xa00 [ocfs2] ocfs2_get_parent+0xba/0x3e0 [ocfs2] reconnect_path+0xb5/0x300 exportfs_decode_fh+0xf6/0x2b0 fh_verify+0x350/0x660 [nfsd] nfsd4_putfh+0x4d/0x60 [nfsd] nfsd4_proc_compound+0x3d3/0x6f0 [nfsd] nfsd_dispatch+0xe0/0x290 [nfsd] svc_process_common+0x412/0x6a0 [sunrpc] svc_process+0x123/0x210 [sunrpc] nfsd+0xff/0x170 [nfsd] kthread+0xcb/0xf0 ret_from_fork+0x61/0x90 Code: 83 c2 02 0f b7 f2 e8 18 dc 91 ff 66 90 eb bf 0f 1f 40 00 55 48 89 e5 41 56 41 55 41 54 53 0f 1f 44 00 00 48 89 fb ba 00 00 02 00 <f0> 0f c1 17 89 d0 45 31 e4 45 31 ed c1 e8 10 66 39 d0 41 89 c6 RIP _raw_spin_lock+0x18/0xf0 CR2: 0000000000001088 ---[ end trace 7264463cd1aac8f9 ]--- Kernel panic - not syncing: Fatal exception Link: http://lkml.kernel.org/r/20200616183829.87211-4-junxiao.bi@oracle.comSigned-off-by: Junxiao Bi <junxiao.bi@oracle.com> Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com> Cc: Changwei Ge <gechangwei@live.cn> Cc: Gang He <ghe@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Jun Piao <piaojun@huawei.com> Cc: Mark Fasheh <mark@fasheh.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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Junxiao Bi authored
Set global_inode_alloc as OCFS2_FIRST_ONLINE_SYSTEM_INODE, that will make it load during mount. It can be used to test whether some global/system inodes are valid. One use case is that nfsd will test whether root inode is valid. Link: http://lkml.kernel.org/r/20200616183829.87211-3-junxiao.bi@oracle.comSigned-off-by: Junxiao Bi <junxiao.bi@oracle.com> Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com> Cc: Changwei Ge <gechangwei@live.cn> Cc: Gang He <ghe@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Jun Piao <piaojun@huawei.com> Cc: Mark Fasheh <mark@fasheh.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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Junxiao Bi authored
Patch series "ocfs2: fix nfsd over ocfs2 issues", v2. This is a series of patches to fix issues on nfsd over ocfs2. patch 1 is to avoid inode removed while nfsd access it patch 2 & 3 is to fix a panic issue. This patch (of 4): When nfsd is getting file dentry using handle or parent dentry of some dentry, one cluster lock is used to avoid inode removed from other node, but it still could be removed from local node, so use a rw lock to avoid this. Link: http://lkml.kernel.org/r/20200616183829.87211-1-junxiao.bi@oracle.com Link: http://lkml.kernel.org/r/20200616183829.87211-2-junxiao.bi@oracle.comSigned-off-by: Junxiao Bi <junxiao.bi@oracle.com> Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com> Cc: Changwei Ge <gechangwei@live.cn> Cc: Gang He <ghe@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Jun Piao <piaojun@huawei.com> Cc: Mark Fasheh <mark@fasheh.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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Lianbo Jiang authored
Signature verification is an important security feature, to protect system from being attacked with a kernel of unknown origin. Kexec rebooting is a way to replace the running kernel, hence need be secured carefully. In the current code of handling signature verification of kexec kernel, the logic is very twisted. It mixes signature verification, IMA signature appraising and kexec lockdown. If there is no KEXEC_SIG_FORCE, kexec kernel image doesn't have one of signature, the supported crypto, and key, we don't think this is wrong, Unless kexec lockdown is executed. IMA is considered as another kind of signature appraising method. If kexec kernel image has signature/crypto/key, it has to go through the signature verification and pass. Otherwise it's seen as verification failure, and won't be loaded. Seems kexec kernel image with an unqualified signature is even worse than those w/o signature at all, this sounds very unreasonable. E.g. If people get a unsigned kernel to load, or a kernel signed with expired key, which one is more dangerous? So, here, let's simplify the logic to improve code readability. If the KEXEC_SIG_FORCE enabled or kexec lockdown enabled, signature verification is mandated. Otherwise, we lift the bar for any kernel image. Link: http://lkml.kernel.org/r/20200602045952.27487-1-lijiang@redhat.comSigned-off-by: Lianbo Jiang <lijiang@redhat.com> Reviewed-by: Jiri Bohac <jbohac@suse.cz> Acked-by: Dave Young <dyoung@redhat.com> Acked-by: Baoquan He <bhe@redhat.com> Cc: James Morris <jmorris@namei.org> Cc: Matthew Garrett <mjg59@google.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Vlastimil Babka authored
Hugh reports: "While stressing compaction, one run oopsed on NULL capc->cc in __free_one_page()'s task_capc(zone): compact_zone_order() had been interrupted, and a page was being freed in the return from interrupt. Though you would not expect it from the source, both gccs I was using (4.8.1 and 7.5.0) had chosen to compile compact_zone_order() with the ".cc = &cc" implemented by mov %rbx,-0xb0(%rbp) immediately before callq compact_zone - long after the "current->capture_control = &capc". An interrupt in between those finds capc->cc NULL (zeroed by an earlier rep stos). This could presumably be fixed by a barrier() before setting current->capture_control in compact_zone_order(); but would also need more care on return from compact_zone(), in order not to risk leaking a page captured by interrupt just before capture_control is reset. Maybe that is the preferable fix, but I felt safer for task_capc() to exclude the rather surprising possibility of capture at interrupt time" I have checked that gcc10 also behaves the same. The advantage of fix in compact_zone_order() is that we don't add another test in the page freeing hot path, and that it might prevent future problems if we stop exposing pointers to uninitialized structures in current task. So this patch implements the suggestion for compact_zone_order() with barrier() (and WRITE_ONCE() to prevent store tearing) for setting current->capture_control, and prevents page leaking with WRITE_ONCE/READ_ONCE in the proper order. Link: http://lkml.kernel.org/r/20200616082649.27173-1-vbabka@suse.cz Fixes: 5e1f0f09 ("mm, compaction: capture a page under direct compaction") Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Reported-by: Hugh Dickins <hughd@google.com> Suggested-by: Hugh Dickins <hughd@google.com> Acked-by: Hugh Dickins <hughd@google.com> Cc: Alex Shi <alex.shi@linux.alibaba.com> Cc: Li Wang <liwang@redhat.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: <stable@vger.kernel.org> [5.1+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Michal Hocko authored
do_swap_page() returns error codes from the VM_FAULT* space. try_charge() might return -ENOMEM, though, and then do_swap_page() simply returns 0 which means a success. We almost never return ENOMEM for GFP_KERNEL single page charge. Except for async OOM handling (oom_disabled v1). So this needs translation to VM_FAULT_OOM otherwise the the page fault path will not notify the userspace and wait for an action. Link: http://lkml.kernel.org/r/20200617090238.GL9499@dhcp22.suse.cz Fixes: 4c6355b2 ("mm: memcontrol: charge swapin pages on instantiation") Signed-off-by: Michal Hocko <mhocko@suse.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Alex Shi <alex.shi@linux.alibaba.com> Cc: Joonsoo Kim <js1304@gmail.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Cc: Roman Gushchin <guro@fb.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Stafford Horne authored
Since v5.8-rc1 OpenRISC Linux fails to boot when DEBUG_VM is enabled. This has been bisected to commit 42fc5414 ("mmap locking API: add mmap_assert_locked() and mmap_assert_write_locked()"). The added locking checks exposed the issue that OpenRISC was not taking this mmap lock when during page walks for DMA operations. This patch locks and unlocks the mmap lock for page walking. Link: http://lkml.kernel.org/r/20200617090247.1680188-1-shorne@gmail.com Fixes: 42fc5414 ("mmap locking API: add mmap_assert_locked() and mmap_assert_write_locked()" Signed-off-by: Stafford Horne <shorne@gmail.com> Reviewed-by: Michel Lespinasse <walken@google.com> Cc: Jonas Bonn <jonas@southpole.se> Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Steven Price <steven.price@arm.com> Cc: Thomas Hellstrom <thellstrom@vmware.com> Cc: Robin Murphy <robin.murphy@arm.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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- 25 Jun, 2020 3 commits
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git://git.kernel.org/pub/scm/linux/kernel/git/s390/linuxLinus Torvalds authored
Pull s390 fixes from Heiko Carstens: - Fix kernel crash on system call single stepping. - Make sure early program check handler is executed with DAT on to avoid an endless program check loop. - Add __GFP_NOWARN flag to debug feature to avoid user triggerable allocation failure messages. * tag 's390-5.8-3' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: s390/debug: avoid kernel warning on too large number of pages s390/kasan: fix early pgm check handler execution s390: fix system call single stepping
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git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/soundLinus Torvalds authored
Pull sound fixes from Takashi Iwai: "A collection of small fixes gathered in the last two weeks. The major changes here are fixes for the recent DPCM regressions found on i.MX and Qualcomm platforms and fixes for resource leaks in ASoC DAI registrations. Other than those are mostly device-specific fixes including the usual USB- and HD-audio quirks, and a fix for syzkaller case and ID updates for new Intel platforms" * tag 'sound-5.8-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (32 commits) ALSA: usb-audio: Fix OOB access of mixer element list ALSA: usb-audio: add quirk for Samsung USBC Headset (AKG) ALSA: usb-audio: Add registration quirk for Kingston HyperX Cloud Flight S ASoC: rockchip: Fix a reference count leak. ASoC: amd: closing specific instance. ALSA: hda: Intel: add missing PCI IDs for ICL-H, TGL-H and EKL ASoC: hdac_hda: fix memleak with regmap not freed on remove ASoC: SOF: Intel: add PCI IDs for ICL-H and TGL-H ASoC: SOF: Intel: add PCI ID for CometLake-S ASoC: Intel: SOF: merge COMETLAKE_LP and COMETLAKE_H ALSA: hda/realtek: Add mute LED and micmute LED support for HP systems ALSA: usb-audio: Fix potential use-after-free of streams ALSA: hda/realtek - Add quirk for MSI GE63 laptop ASoC: fsl_ssi: Fix bclk calculation for mono channel ASoC: SOF: Intel: hda: Clear RIRB status before reading WP ASoC: rt1015: Update rt1015 default register value according to spec modification. ASoC: qcom: common: set correct directions for dailinks ASoc: q6afe: add support to get port direction ASoC: soc-pcm: fix checks for multi-cpu FE dailinks ASoC: rt5682: Let dai clks be registered whether mclk exists or not ...
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git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofsLinus Torvalds authored
Pull erofs fix from Gao Xiang: "Fix a regression which uses potential uninitialized high 32-bit value unexpectedly recently observed with specific compiler options" * tag 'erofs-for-5.8-rc3-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs: erofs: fix partially uninitialized misuse in z_erofs_onlinepage_fixup
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- 24 Jun, 2020 4 commits
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git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhostLinus Torvalds authored
Pull virtio fixes from Michael Tsirkin: "Fixes all over the place. This includes a couple of tests that I would normally defer, but since they have already been helpful in catching some bugs, don't build for any users at all, and having them upstream makes life easier for everyone, I think it's ok even at this late stage" * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: tools/virtio: Use tools/include/list.h instead of stubs tools/virtio: Reset index in virtio_test --reset. tools/virtio: Extract virtqueue initialization in vq_reset tools/virtio: Use __vring_new_virtqueue in virtio_test.c tools/virtio: Add --reset tools/virtio: Add --batch=random option tools/virtio: Add --batch option virtio-mem: add memory via add_memory_driver_managed() virtio-mem: silence a static checker warning vhost_vdpa: Fix potential underflow in vhost_vdpa_mmap() vdpa: fix typos in the comments for __vdpa_alloc_device()
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git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linuxLinus Torvalds authored
Pull thread fix from Christian Brauner: "This fixes a regression introduced with 303cc571 ("nsproxy: attach to namespaces via pidfds"). The LTP testsuite reported a regression where users would now see EBADF returned instead of EINVAL when an fd was passed that referred to an open file but the file was not a namespace file. Fix this by continuing to report EINVAL and add a regression test" * tag 'for-linus-2020-06-24' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux: tests: test for setns() EINVAL regression nsproxy: restore EINVAL for non-namespace file descriptor
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Takashi Iwai authored
The USB-audio mixer code holds a linked list of usb_mixer_elem_list, and several operations are performed for each mixer element. A few of them (snd_usb_mixer_notify_id() and snd_usb_mixer_interrupt_v2()) assume each mixer element being a usb_mixer_elem_info object that is a subclass of usb_mixer_elem_list, cast via container_of() and access it members. This may result in an out-of-bound access when a non-standard list element has been added, as spotted by syzkaller recently. This patch adds a new field, is_std_info, in usb_mixer_elem_list to indicate that the element is the usb_mixer_elem_info type or not, and skip the access to such an element if needed. Reported-by: syzbot+fb14314433463ad51625@syzkaller.appspotmail.com Reported-by: syzbot+2405ca3401e943c538b5@syzkaller.appspotmail.com Cc: <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20200624122340.9615-1-tiwai@suse.deSigned-off-by: Takashi Iwai <tiwai@suse.de>
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Gao Xiang authored
Hongyu reported "id != index" in z_erofs_onlinepage_fixup() with specific aarch64 environment easily, which wasn't shown before. After digging into that, I found that high 32 bits of page->private was set to 0xaaaaaaaa rather than 0 (due to z_erofs_onlinepage_init behavior with specific compiler options). Actually we only use low 32 bits to keep the page information since page->private is only 4 bytes on most 32-bit platforms. However z_erofs_onlinepage_fixup() uses the upper 32 bits by mistake. Let's fix it now. Reported-and-tested-by: Hongyu Jin <hongyu.jin@unisoc.com> Fixes: 3883a79a ("staging: erofs: introduce VLE decompression support") Cc: <stable@vger.kernel.org> # 4.19+ Reviewed-by: Chao Yu <yuchao0@huawei.com> Link: https://lore.kernel.org/r/20200618234349.22553-1-hsiangkao@aol.comSigned-off-by: Gao Xiang <hsiangkao@redhat.com>
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- 23 Jun, 2020 11 commits
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git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds authored
Pull kvm fixes from Paolo Bonzini: "All bugfixes except for a couple cleanup patches" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: VMX: Remove vcpu_vmx's defunct copy of host_pkru KVM: x86: allow TSC to differ by NTP correction bounds without TSC scaling KVM: X86: Fix MSR range of APIC registers in X2APIC mode KVM: VMX: Stop context switching MSR_IA32_UMWAIT_CONTROL KVM: nVMX: Plumb L2 GPA through to PML emulation KVM: x86/mmu: Avoid mixing gpa_t with gfn_t in walk_addr_generic() KVM: LAPIC: ensure APIC map is up to date on concurrent update requests kvm: lapic: fix broken vcpu hotplug Revert "KVM: VMX: Micro-optimize vmexit time when not exposing PMU" KVM: VMX: Add helpers to identify interrupt type from intr_info kvm/svm: disable KCSAN for svm_vcpu_run() KVM: MIPS: Fix a build error for !CPU_LOONGSON64
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git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linuxLinus Torvalds authored
Pull btrfs fixes from David Sterba: "A number of fixes, located in two areas, one performance fix and one fixup for better integration with another patchset. - bug fixes in nowait aio: - fix snapshot creation hang after nowait-aio was used - fix failure to write to prealloc extent past EOF - don't block when extent range is locked - block group fixes: - relocation failure when scrub runs in parallel - refcount fix when removing fails - fix race between removal and creation - space accounting fixes - reinstante fast path check for log tree at unlink time, fixes performance drop up to 30% in REAIM - kzfree/kfree fixup to ease treewide patchset renaming kzfree" * tag 'for-5.8-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: use kfree() in btrfs_ioctl_get_subvol_info() btrfs: fix RWF_NOWAIT writes blocking on extent locks and waiting for IO btrfs: fix RWF_NOWAIT write not failling when we need to cow btrfs: fix failure of RWF_NOWAIT write into prealloc extent beyond eof btrfs: fix hang on snapshot creation after RWF_NOWAIT write btrfs: check if a log root exists before locking the log_mutex on unlink btrfs: fix bytes_may_use underflow when running balance and scrub in parallel btrfs: fix data block group relocation failure due to concurrent scrub btrfs: fix race between block group removal and block group creation btrfs: fix a block group ref counter leak after failure to remove block group
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Macpaul Lin authored
We've found Samsung USBC Headset (AKG) (VID: 0x04e8, PID: 0xa051) need a tiny delay after each class compliant request. Otherwise the device might not be able to be recognized each times. Signed-off-by: Chihhao Chen <chihhao.chen@mediatek.com> Signed-off-by: Macpaul Lin <macpaul.lin@mediatek.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/1592910203-24035-1-git-send-email-macpaul.lin@mediatek.comSigned-off-by: Takashi Iwai <tiwai@suse.de>
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Christian Borntraeger authored
When specifying insanely large debug buffers a kernel warning is printed. The debug code does handle the error gracefully, though. Instead of duplicating the check let us silence the warning to avoid crashes when panic_on_warn is used. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
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Vasily Gorbik authored
Currently if early_pgm_check_handler is called it ends up in pgm check loop. The problem is that early_pgm_check_handler is instrumented by KASAN but executed without DAT flag enabled which leads to addressing exception when KASAN checks try to access shadow memory. Fix that by executing early handlers with DAT flag on under KASAN as expected. Reported-and-tested-by: Alexander Egorenkov <egorenar@linux.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
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Sven Schnelle authored
When single stepping an svc instruction on s390, the kernel is entered with a PER program check interruption. The program check handler than jumps to the system call handler by reloading the PSW. The code didn't set GPR13 to the thread pointer in struct task_struct. This made the kernel access invalid memory while trying to fetch the syscall function address. Fix this by always assigned GPR13 after .Lsysc_per. Fixes: 0b0ed657 ("s390: remove critical section cleanup from entry.S") Reported-and-tested-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
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Christoffer Nielsen authored
Similar to the Kingston HyperX AMP, the Kingston HyperX Cloud Alpha S (0951:0x16ea) uses two interfaces, but only the second interface contains the capture stream. This patch delays the registration until the second interface appears. Signed-off-by: Christoffer Nielsen <cn@obviux.dk> Cc: <stable@vger.kernel.org> Link: https://lore.kernel.org/r/CAOtG2YHOM3zy+ed9KS-J4HkZo_QGzcUG9MigSp4e4_-13r6B=Q@mail.gmail.comSigned-off-by: Takashi Iwai <tiwai@suse.de>
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Sean Christopherson authored
Remove vcpu_vmx.host_pkru, which got left behind when PKRU support was moved to common x86 code. No functional change intended. Fixes: 37486135 ("KVM: x86: Fix pkru save/restore when guest CR4.PKE=0, move it to x86.c") Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Message-Id: <20200617034123.25647-1-sean.j.christopherson@intel.com> Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: Jim Mattson <jmattson@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Marcelo Tosatti authored
The Linux TSC calibration procedure is subject to small variations (its common to see +-1 kHz difference between reboots on a given CPU, for example). So migrating a guest between two hosts with identical processor can fail, in case of a small variation in calibrated TSC between them. Without TSC scaling, the current kernel interface will either return an error (if user_tsc_khz <= tsc_khz) or enable TSC catchup mode. This change enables the following TSC tolerance check to accept KVM_SET_TSC_KHZ within tsc_tolerance_ppm (which is 250ppm by default). /* * Compute the variation in TSC rate which is acceptable * within the range of tolerance and decide if the * rate being applied is within that bounds of the hardware * rate. If so, no scaling or compensation need be done. */ thresh_lo = adjust_tsc_khz(tsc_khz, -tsc_tolerance_ppm); thresh_hi = adjust_tsc_khz(tsc_khz, tsc_tolerance_ppm); if (user_tsc_khz < thresh_lo || user_tsc_khz > thresh_hi) { pr_debug("kvm: requested TSC rate %u falls outside tolerance [%u,%u]\n", user_tsc_khz, thresh_lo, thresh_hi); use_scaling = 1; } NTP daemon in the guest can correct this difference (NTP can correct upto 500ppm). Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Message-Id: <20200616114741.GA298183@fuller.cnet> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Xiaoyao Li authored
Only MSR address range 0x800 through 0x8ff is architecturally reserved and dedicated for accessing APIC registers in x2APIC mode. Fixes: 0105d1a5 ("KVM: x2apic interface to lapic") Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com> Message-Id: <20200616073307.16440-1-xiaoyao.li@intel.com> Cc: stable@vger.kernel.org Reviewed-by: Sean Christopherson <sean.j.christopherson@intel.com> Reviewed-by: Jim Mattson <jmattson@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Sean Christopherson authored
Remove support for context switching between the guest's and host's desired UMWAIT_CONTROL. Propagating the guest's value to hardware isn't required for correct functionality, e.g. KVM intercepts reads and writes to the MSR, and the latency effects of the settings controlled by the MSR are not architecturally visible. As a general rule, KVM should not allow the guest to control power management settings unless explicitly enabled by userspace, e.g. see KVM_CAP_X86_DISABLE_EXITS. E.g. Intel's SDM explicitly states that C0.2 can improve the performance of SMT siblings. A devious guest could disable C0.2 so as to improve the performance of their workloads at the detriment to workloads running in the host or on other VMs. Wholesale removal of UMWAIT_CONTROL context switching also fixes a race condition where updates from the host may cause KVM to enter the guest with the incorrect value. Because updates are are propagated to all CPUs via IPI (SMP function callback), the value in hardware may be stale with respect to the cached value and KVM could enter the guest with the wrong value in hardware. As above, the guest can't observe the bad value, but it's a weird and confusing wart in the implementation. Removal also fixes the unnecessary usage of VMX's atomic load/store MSR lists. Using the lists is only necessary for MSRs that are required for correct functionality immediately upon VM-Enter/VM-Exit, e.g. EFER on old hardware, or for MSRs that need to-the-uop precision, e.g. perf related MSRs. For UMWAIT_CONTROL, the effects are only visible in the kernel via TPAUSE/delay(), and KVM doesn't do any form of delay in vcpu_vmx_run(). Using the atomic lists is undesirable as they are more expensive than direct RDMSR/WRMSR. Furthermore, even if giving the guest control of the MSR is legitimate, e.g. in pass-through scenarios, it's not clear that the benefits would outweigh the overhead. E.g. saving and restoring an MSR across a VMX roundtrip costs ~250 cycles, and if the guest diverged from the host that cost would be paid on every run of the guest. In other words, if there is a legitimate use case then it should be enabled by a new per-VM capability. Note, KVM still needs to emulate MSR_IA32_UMWAIT_CONTROL so that it can correctly expose other WAITPKG features to the guest, e.g. TPAUSE, UMWAIT and UMONITOR. Fixes: 6e3ba4ab ("KVM: vmx: Emulate MSR IA32_UMWAIT_CONTROL") Cc: stable@vger.kernel.org Cc: Jingqi Liu <jingqi.liu@intel.com> Cc: Tao Xu <tao3.xu@intel.com> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Message-Id: <20200623005135.10414-1-sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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- 22 Jun, 2020 2 commits
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Sean Christopherson authored
Explicitly pass the L2 GPA to kvm_arch_write_log_dirty(), which for all intents and purposes is vmx_write_pml_buffer(), instead of having the latter pull the GPA from vmcs.GUEST_PHYSICAL_ADDRESS. If the dirty bit update is the result of KVM emulation (rare for L2), then the GPA in the VMCS may be stale and/or hold a completely unrelated GPA. Fixes: c5f983f6 ("nVMX: Implement emulated Page Modification Logging") Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Message-Id: <20200622215832.22090-2-sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Vitaly Kuznetsov authored
translate_gpa() returns a GPA, assigning it to 'real_gfn' seems obviously wrong. There is no real issue because both 'gpa_t' and 'gfn_t' are u64 and we don't use the value in 'real_gfn' as a GFN, we do real_gfn = gpa_to_gfn(real_gfn); instead. 'If you see a "buffalo" sign on an elephant's cage, do not trust your eyes', but let's fix it for good. No functional change intended. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Message-Id: <20200622151435.752560-1-vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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