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Jones" , Mark W , regressions@lists.linux.dev, Johannes Weiner , Yosry Ahmed , Chengming Zhou Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: 875B0100004 X-Stat-Signature: e9tnbbzkh3xrniy5d39gnfidak9su41h X-Rspam-User: X-HE-Tag: 1713305679-639088 X-HE-Meta: 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 yeGzL4CW uuzNmx+mp8DX+4/XPvZfYFDWs9qBch3v2sDzv X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Tue, Apr 16, 2024 at 5:19=E2=80=AFAM Christian Heusel wrote: > > Hello everyone, Thanks for the report, Christian! Looking at it now. > > while rebuilding a few packages in Arch Linux we have recently come > across a regression in the linux kernel which was made visible by a test > failure in libguestfs[0], where the booted kernel showed a Call Trace > like the following one: > > [ 218.738568] CPU: 0 PID: 167 Comm: guestfsd Not tainted 6.7.0-rc4-1-mai= nline-00158-gb5ba474f3f51 #1 bf39861cf50acae7a79c534e25532f28afe4e593^M Is this one of the kernel versions that was broken? That looks a bit odd, as zswap shrinker landed on 6.8... > [ 218.739007] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS A= rch Linux 1.16.3-1-1 04/01/2014^M > [ 218.739787] RIP: 0010:memcg_page_state+0x9/0x30^M > [ 218.740299] Code: 0d b8 ff ff 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 9= 0 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 0f 1f 00 0f 1f 44 00 00 <= 48> 8b 87 00 06 00 00 48 63 f6 31 d2 48 8b 04 f0 48 85 c0 48 0f 48^M > [ 218.740727] RSP: 0018:ffffb5fa808dfc10 EFLAGS: 00000202^M > [ 218.740862] RAX: 0000000000000000 RBX: ffffb5fa808dfce0 RCX: 000000000= 0000002^M > [ 218.741016] RDX: 0000000000000001 RSI: 0000000000000033 RDI: 000000000= 0000000^M > [ 218.741168] RBP: 0000000000000000 R08: ffff976681ff8000 R09: 000000000= 0000000^M > [ 218.741322] R10: 0000000000000001 R11: ffff9766833f9d00 R12: ffff9766f= fffe780^M > [ 218.742167] R13: 0000000000000000 R14: ffff976680cc1800 R15: ffff97668= 2204d80^M > [ 218.742376] FS: 00007f1479d9f540(0000) GS:ffff9766fbc00000(0000) knlG= S:0000000000000000^M > [ 218.742569] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033^M > [ 218.743256] CR2: 0000000000000600 CR3: 0000000103606000 CR4: 000000000= 0750ef0^M > [ 218.743494] PKRU: 55555554^M > [ 218.743593] Call Trace:^M > [ 218.743733] ^M > [ 218.743847] ? __die+0x23/0x70^M > [ 218.743957] ? page_fault_oops+0x171/0x4e0^M > [ 218.744056] ? free_unref_page+0xf6/0x180^M > [ 218.744458] ? exc_page_fault+0x7f/0x180^M > [ 218.744551] ? asm_exc_page_fault+0x26/0x30^M > [ 218.744684] ? memcg_page_state+0x9/0x30^M > [ 218.744779] zswap_shrinker_count+0x9d/0x110^M > [ 218.744896] do_shrink_slab+0x3a/0x360^M > [ 218.744990] shrink_slab+0xc7/0x3c0^M > [ 218.745609] drop_slab+0x85/0x140^M > [ 218.745691] drop_caches_sysctl_handler+0x7e/0xd0^M > [ 218.745799] proc_sys_call_handler+0x1c0/0x2e0^M > [ 218.745912] vfs_write+0x23d/0x400^M > [ 218.745998] ksys_write+0x6f/0xf0^M > [ 218.746080] do_syscall_64+0x64/0xe0^M > [ 218.746169] ? exit_to_user_mode_prepare+0x132/0x1f0^M > [ 218.746873] entry_SYSCALL_64_after_hwframe+0x6e/0x76^M > > The regression is present in the mainline kernel and also was > independently reported to the redhat bugtracker[1]. > > I have bisected (see log[2]) the regression between v6.9-rc4 and v6.6 > and have landed on the following results (removed unrelated test commit) > as remainders since some of the commits were not buildable for me: > - 7108cc3f765c ("mm: memcg: add per-memcg zswap writeback stat") > - a65b0e7607cc ("zswap: make shrinking memcg-aware") > - b5ba474f3f51 ("zswap: shrink zswap pool based on memory pressure")