On Sat, Dec 07, 2024 at 11:15:22AM -0800, syzbot wrote: > Hello, > > syzbot found the following issue on: > > HEAD commit: af2ea8ab7a54 Add linux-next specific files for 20241205 > git tree: linux-next > console+strace: https://syzkaller.appspot.com/x/log.txt?x=1210e8df980000 > kernel config: https://syzkaller.appspot.com/x/.config?x=76f158395f6f15fd > dashboard link: https://syzkaller.appspot.com/bug?extid=67a21f2b4c8e9e650adf > compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=111050f8580000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=136fade8580000 > > Downloadable assets: > disk image: https://storage.googleapis.com/syzbot-assets/8af0861258fa/disk-af2ea8ab.raw.xz > vmlinux: https://storage.googleapis.com/syzbot-assets/ffb38cf7a344/vmlinux-af2ea8ab.xz > kernel image: https://storage.googleapis.com/syzbot-assets/6fbd2e50358a/bzImage-af2ea8ab.xz > > The issue was bisected to: > > commit 51ac493f56fa00b052be4fbc94ac91f057ebc2e7 > Author: Yu Zhao <yuzhao@xxxxxxxxxx> > Date: Mon Dec 2 03:28:19 2024 +0000 > > mm/mglru: optimize deactivation > > bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=141418df980000 > final oops: https://syzkaller.appspot.com/x/report.txt?x=161418df980000 > console output: https://syzkaller.appspot.com/x/log.txt?x=121418df980000 > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+67a21f2b4c8e9e650adf@xxxxxxxxxxxxxxxxxxxxxxxxx > Fixes: 51ac493f56fa ("mm/mglru: optimize deactivation") > > __kernel_write_iter+0x42a/0x940 fs/read_write.c:612 > __kernel_write fs/read_write.c:632 [inline] > kernel_write+0x214/0x330 fs/read_write.c:653 > process_sysctl_arg+0x3f7/0x650 fs/proc/proc_sysctl.c:1683 > parse_one kernel/params.c:153 [inline] > parse_args+0x623/0xdc0 kernel/params.c:186 > do_sysctl_args+0xeb/0x180 fs/proc/proc_sysctl.c:1715 > kernel_init+0x80/0x2b0 init/main.c:1489 > ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 > page_owner free stack trace missing > ------------[ cut here ]------------ > WARNING: CPU: 0 PID: 5828 at ./include/linux/memcontrol.h:730 folio_lruvec include/linux/memcontrol.h:730 [inline] > WARNING: CPU: 0 PID: 5828 at ./include/linux/memcontrol.h:730 lru_gen_clear_refs+0x498/0x520 mm/swap.c:410 > Modules linked in: > CPU: 0 UID: 0 PID: 5828 Comm: syz-executor425 Not tainted 6.13.0-rc1-next-20241205-syzkaller #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 > RIP: 0010:folio_lruvec include/linux/memcontrol.h:730 [inline] > RIP: 0010:lru_gen_clear_refs+0x498/0x520 mm/swap.c:410 > Code: 66 ff ff ff e8 99 dc c2 ff e9 92 fe ff ff e8 8f dc c2 ff 4c 89 e7 48 c7 c6 20 c9 13 8c e8 20 95 0c 00 c6 05 4c 86 27 0e 01 90 <0f> 0b 90 e9 7b fc ff ff 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c 43 fd > RSP: 0018:ffffc90003787460 EFLAGS: 00010246 > RAX: dc5da43f42521400 RBX: 0000000000000000 RCX: ffffc90003787003 > RDX: 0000000000000002 RSI: ffffffff8c0aa440 RDI: ffffffff8c5fbe80 > RBP: ffffc90003787530 R08: ffffffff9019d9b7 R09: 1ffffffff2033b36 > R10: dffffc0000000000 R11: fffffbfff2033b37 R12: ffffea00006a8000 > R13: 1ffffd40000d5000 R14: 00fff00000000058 R15: 0000000000000000 > FS: 0000555587a6b380(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 0000000020000040 CR3: 000000007213e000 CR4: 00000000003526f0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > Call Trace: > <TASK> > deactivate_file_folio+0x99/0x100 mm/swap.c:679 > mapping_try_invalidate+0x28b/0x550 mm/truncate.c:489 > drop_pagecache_sb+0x1ab/0x260 fs/drop_caches.c:40 > iterate_supers+0xc6/0x190 fs/super.c:934 > drop_caches_sysctl_handler+0x8c/0x160 fs/drop_caches.c:64 > proc_sys_call_handler+0x5ec/0x920 fs/proc/proc_sysctl.c:601 > do_iter_readv_writev+0x600/0x880 > vfs_writev+0x376/0xba0 fs/read_write.c:1050 > do_writev+0x1b6/0x360 fs/read_write.c:1096 > do_syscall_x64 arch/x86/entry/common.c:52 [inline] > do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 > entry_SYSCALL_64_after_hwframe+0x77/0x7f > RIP: 0033:0x7f625e20b329 > Code: 48 83 c4 28 c3 e8 37 17 00 00 0f 1f 80 00 00 00 00 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:00007ffc4d77ac58 EFLAGS: 00000246 ORIG_RAX: 0000000000000014 > RAX: ffffffffffffffda RBX: 00007ffc4d77ae28 RCX: 00007f625e20b329 > RDX: 0000000000000001 RSI: 00000000200000c0 RDI: 0000000000000003 > RBP: 00007f625e27e610 R08: 0000000000000000 R09: 00007ffc4d77ae28 > R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 > R13: 00007ffc4d77ae18 R14: 0000000000000001 R15: 0000000000000001 > </TASK> > > > --- > This report is generated by a bot. It may contain errors. > See https://goo.gl/tpsmEJ for more information about syzbot. > syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. > > syzbot will keep track of this issue. See: > https://goo.gl/tpsmEJ#status for how to communicate with syzbot. > For information about bisection process see: https://goo.gl/tpsmEJ#bisection > > If the report is already addressed, let syzbot know by replying with: > #syz fix: exact-commit-title > > If you want syzbot to run the reproducer, reply with: > #syz test: git://repo/address.git branch-or-commit-hash > If you attach or paste a git patch, syzbot will apply it before testing. #syz test: git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-unstable diff --git a/mm/swap.c b/mm/swap.c index 320b959b74c6..062c8565b899 100644 --- a/mm/swap.c +++ b/mm/swap.c @@ -384,7 +384,7 @@ static void lru_gen_inc_refs(struct folio *folio) { unsigned long new_flags, old_flags = READ_ONCE(folio->flags); - if (folio_test_unevictable(folio)) + if (!folio_test_lru(folio) || folio_test_unevictable(folio)) return; /* see the comment on LRU_REFS_FLAGS */ @@ -405,14 +405,17 @@ static void lru_gen_inc_refs(struct folio *folio) static bool lru_gen_clear_refs(struct folio *folio) { - int gen = folio_lru_gen(folio); + struct lru_gen_folio *lrugen; int type = folio_is_file_lru(folio); - struct lru_gen_folio *lrugen = &folio_lruvec(folio)->lrugen; + + if (!folio_test_lru(folio) || folio_test_unevictable(folio)) + return true; set_mask_bits(&folio->flags, LRU_REFS_FLAGS | BIT(PG_workingset), 0); + lrugen = &folio_lruvec(folio)->lrugen; /* whether can do without shuffling under the LRU lock */ - return gen == lru_gen_from_seq(READ_ONCE(lrugen->min_seq[type])); + return folio_lru_gen(folio) == lru_gen_from_seq(READ_ONCE(lrugen->min_seq[type])); } #else /* !CONFIG_LRU_GEN */
