user/sven/linux.git/include/linux/gfp.h, branch v6.1.37

mm: replace VM_WARN_ON to pr_warn if the node is offline with __GFP_THISNODE

2022-11-30T22:49:40Z

Syzbot reported the below splat: WARNING: CPU: 1 PID: 3646 at include/linux/gfp.h:221 __alloc_pages_node include/linux/gfp.h:221 [inline] WARNING: CPU: 1 PID: 3646 at include/linux/gfp.h:221 hpage_collapse_alloc_page mm/khugepaged.c:807 [inline] WARNING: CPU: 1 PID: 3646 at include/linux/gfp.h:221 alloc_charge_hpage+0x802/0xaa0 mm/khugepaged.c:963 Modules linked in: CPU: 1 PID: 3646 Comm: syz-executor210 Not tainted 6.1.0-rc1-syzkaller-00454-ga70385240892 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/11/2022 RIP: 0010:__alloc_pages_node include/linux/gfp.h:221 [inline] RIP: 0010:hpage_collapse_alloc_page mm/khugepaged.c:807 [inline] RIP: 0010:alloc_charge_hpage+0x802/0xaa0 mm/khugepaged.c:963 Code: e5 01 4c 89 ee e8 6e f9 ae ff 4d 85 ed 0f 84 28 fc ff ff e8 70 fc ae ff 48 8d 6b ff 4c 8d 63 07 e9 16 fc ff ff e8 5e fc ae ff <0f> 0b e9 96 fa ff ff 41 bc 1a 00 00 00 e9 86 fd ff ff e8 47 fc ae RSP: 0018:ffffc90003fdf7d8 EFLAGS: 00010293 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff888077f457c0 RSI: ffffffff81cd8f42 RDI: 0000000000000001 RBP: ffff888079388c0c R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 00007f6b48ccf700(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f6b48a819f0 CR3: 00000000171e7000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: collapse_file+0x1ca/0x5780 mm/khugepaged.c:1715 hpage_collapse_scan_file+0xd6c/0x17a0 mm/khugepaged.c:2156 madvise_collapse+0x53a/0xb40 mm/khugepaged.c:2611 madvise_vma_behavior+0xd0a/0x1cc0 mm/madvise.c:1066 madvise_walk_vmas+0x1c7/0x2b0 mm/madvise.c:1240 do_madvise.part.0+0x24a/0x340 mm/madvise.c:1419 do_madvise mm/madvise.c:1432 [inline] __do_sys_madvise mm/madvise.c:1432 [inline] __se_sys_madvise mm/madvise.c:1430 [inline] __x64_sys_madvise+0x113/0x150 mm/madvise.c:1430 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f6b48a4eef9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 b1 15 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f6b48ccf318 EFLAGS: 00000246 ORIG_RAX: 000000000000001c RAX: ffffffffffffffda RBX: 00007f6b48af0048 RCX: 00007f6b48a4eef9 RDX: 0000000000000019 RSI: 0000000000600003 RDI: 0000000020000000 RBP: 00007f6b48af0040 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f6b48aa53a4 R13: 00007f6b48bffcbf R14: 00007f6b48ccf400 R15: 0000000000022000 It is because khugepaged allocates pages with __GFP_THISNODE, but the preferred node is bogus. The previous patch fixed the khugepaged code to avoid allocating page from non-existing node. But it is still racy against memory hotremove. There is no synchronization with the memory hotplug so it is possible that memory gets offline during a longer taking scanning. So this warning still seems not quite helpful because: * There is no guarantee the node is online for __GFP_THISNODE context for all the callsites. * Kernel just fails the allocation regardless the warning, and it looks all callsites handle the allocation failure gracefully. Although while the warning has helped to identify a buggy code, it is not safe in general and this warning could panic the system with panic-on-warn configuration which tends to be used surprisingly often. So replace VM_WARN_ON to pr_warn(). And the warning will be triggered if __GFP_NOWARN is set since the allocator would print out warning for such case if __GFP_NOWARN is not set. [shy828301@gmail.com: rename nid to this_node and gfp to warn_gfp] Link: https://lkml.kernel.org/r/20221123193014.153983-1-shy828301@gmail.com [akpm@linux-foundation.org: fix whitespace] [akpm@linux-foundation.org: print gfp_mask instead of warn_gfp, per Michel] Link: https://lkml.kernel.org/r/20221108184357.55614-3-shy828301@gmail.com Fixes: 7d8faaf15545 ("mm/madvise: introduce MADV_COLLAPSE sync hugepage collapse") Signed-off-by: Yang Shi Reported-by: Suggested-by: Michal Hocko Acked-by: Michal Hocko Cc: Zach O'Keefe Signed-off-by: Andrew Morton

mm/page_alloc: remove obsolete gfpflags_normal_context()

2022-10-03T21:03:30Z

Since commit dacb5d8875cc ("tcp: fix page frag corruption on page fault"), there's no caller of gfpflags_normal_context(). Remove it as this helper is strictly tied to the sk page frag usage and there won't be other user in the future. [linmiaohe@huawei.com: fix htmldocs] Link: https://lkml.kernel.org/r/1bc55727-9b66-0e9e-c306-f10c4716ea89@huawei.com Link: https://lkml.kernel.org/r/20220916072257.9639-16-linmiaohe@huawei.com Signed-off-by: Miaohe Lin Reviewed-by: David Hildenbrand Reviewed-by: Anshuman Khandual Reviewed-by: Oscar Salvador Cc: Matthew Wilcox Signed-off-by: Andrew Morton

mm: add more BUILD_BUG_ONs to gfp_migratetype()

2022-09-12T03:25:53Z

gfp_migratetype() also expects GFP_RECLAIMABLE and GFP_MOVABLE|GFP_RECLAIMABLE to be shiftable into MIGRATE_* enum values, so add some more BUILD_BUG_ONs to reflect this assumption. Link: https://linux-review.googlesource.com/id/Iae64e2182f75c3aca776a486b71a72571d66d83e Link: https://lkml.kernel.org/r/20220726230241.3770532-1-pcc@google.com Signed-off-by: Peter Collingbourne Signed-off-by: Andrew Morton

headers/deps: mm: Split out of

2022-07-15T13:35:54Z

This is a much smaller header. Signed-off-by: Ingo Molnar Signed-off-by: Yury Norov

headers/deps: mm: Optimize header dependencies

2022-07-15T13:35:54Z

There's a couple of superfluous inclusions here - remove them before doing bigger changes. Signed-off-by: Ingo Molnar Signed-off-by: Yury Norov

tracing: incorrect gfp_t conversion

2022-05-13T14:20:18Z

Fixes the following sparse warnings: include/trace/events/*: sparse: cast to restricted gfp_t include/trace/events/*: sparse: restricted gfp_t degrades to integer gfp_t type is bitwise and requires __force attributes for any casts. Link: https://lkml.kernel.org/r/331d88fe-f4f7-657c-02a2-d977f15fbff6@openvz.org Signed-off-by: Vasily Averin Cc: Steven Rostedt Cc: Ingo Molnar Signed-off-by: Andrew Morton

mm: remove alloc_pages_vma()

2022-05-13T14:20:15Z

All callers have now been converted to use vma_alloc_folio(), so convert the body of alloc_pages_vma() to allocate folios instead. Link: https://lkml.kernel.org/r/20220504182857.4013401-5-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) Reviewed-by: Christoph Hellwig Signed-off-by: Andrew Morton

mm: Add vma_alloc_folio()

2022-04-07T13:43:41Z

This wrapper around alloc_pages_vma() calls prep_transhuge_page(), removing the obligation from the caller. This is in the same spirit as __folio_alloc(). Signed-off-by: Matthew Wilcox (Oracle) Reviewed-by: Zi Yan Reviewed-by: William Kucharski

mm, kasan: fix __GFP_BITS_SHIFT definition breaking LOCKDEP

2022-04-01T18:46:09Z

KASAN changes that added new GFP flags mistakenly updated __GFP_BITS_SHIFT as the total number of GFP bits instead of as a shift used to define __GFP_BITS_MASK. This broke LOCKDEP, as __GFP_BITS_MASK now gets the 25th bit enabled instead of the 28th for __GFP_NOLOCKDEP. Update __GFP_BITS_SHIFT to always count KASAN GFP bits. In the future, we could handle all combinations of KASAN and LOCKDEP to occupy as few bits as possible. For now, we have enough GFP bits to be inefficient in this quick fix. Link: https://lkml.kernel.org/r/462ff52742a1fcc95a69778685737f723ee4dfb3.1648400273.git.andreyknvl@google.com Fixes: 9353ffa6e9e9 ("kasan, page_alloc: allow skipping memory init for HW_TAGS") Fixes: 53ae233c30a6 ("kasan, page_alloc: allow skipping unpoisoning for HW_TAGS") Fixes: f49d9c5bb15c ("kasan, mm: only define ___GFP_SKIP_KASAN_POISON with HW_TAGS") Signed-off-by: Andrey Konovalov Reported-by: Sebastian Andrzej Siewior Tested-by: Sebastian Andrzej Siewior Acked-by: Vlastimil Babka Cc: Marco Elver Cc: Alexander Potapenko Cc: Dmitry Vyukov Cc: Andrey Ryabinin Cc: Matthew Wilcox Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

kasan, page_alloc: allow skipping memory init for HW_TAGS

2022-03-25T02:06:47Z

Add a new GFP flag __GFP_SKIP_ZERO that allows to skip memory initialization. The flag is only effective with HW_TAGS KASAN. This flag will be used by vmalloc code for page_alloc allocations backing vmalloc() mappings in a following patch. The reason to skip memory initialization for these pages in page_alloc is because vmalloc code will be initializing them instead. With the current implementation, when __GFP_SKIP_ZERO is provided, __GFP_ZEROTAGS is ignored. This doesn't matter, as these two flags are never provided at the same time. However, if this is changed in the future, this particular implementation detail can be changed as well. Link: https://lkml.kernel.org/r/0d53efeff345de7d708e0baa0d8829167772521e.1643047180.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov Acked-by: Marco Elver Cc: Alexander Potapenko Cc: Andrey Ryabinin Cc: Catalin Marinas Cc: Dmitry Vyukov Cc: Evgenii Stepanov Cc: Mark Rutland Cc: Peter Collingbourne Cc: Vincenzo Frascino Cc: Will Deacon Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds