On 16.02.24 08:33, Byungchul Park wrote:
Changes from v1: 1. Trim the verbose oops in the commit message. (feedbacked by Phil Auld) 2. Rewrite a comment in code. (feedbacked by Phil Auld) --->8--- From 6830b59db267a31b78f6f09af12ae0e3132b4bca Mon Sep 17 00:00:00 2001 From: Byungchul Park <byungchul@xxxxxx> Date: Fri, 16 Feb 2024 16:26:23 +0900 Subject: [PATCH v2] sched/numa, mm: do not promote folios to nodes not set N_MEMORY While running qemu with a configuration where some CPUs don't have their local memory and with a kernel numa balancing on, the following oops has been observed. It's because of null pointers of ->zone_pgdat of zones of those nodes that are not initialized properly at booting time. So should avoid nodes not set N_MEMORY from getting promoted.BUG: unable to handle page fault for address: 00000000000033f3 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP NOPTI CPU: 2 PID: 895 Comm: masim Not tainted 6.6.0-dirty #255 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014 RIP: 0010:wakeup_kswapd (./linux/mm/vmscan.c:7812) Code: (omitted) RSP: 0000:ffffc90004257d58 EFLAGS: 00010286 RAX: ffffffffffffffff RBX: ffff88883fff0480 RCX: 0000000000000003 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88883fff0480 RBP: ffffffffffffffff R08: ff0003ffffffffff R09: ffffffffffffffff R10: ffff888106c95540 R11: 0000000055555554 R12: 0000000000000003 R13: 0000000000000000 R14: 0000000000000000 R15: ffff88883fff0940 FS: 00007fc4b8124740(0000) GS:ffff888827c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000000033f3 CR3: 000000026cc08004 CR4: 0000000000770ee0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: <TASK> ? __die ? page_fault_oops ? __pte_offset_map_lock ? exc_page_fault ? asm_exc_page_fault ? wakeup_kswapd migrate_misplaced_page __handle_mm_fault handle_mm_fault do_user_addr_fault exc_page_fault asm_exc_page_fault RIP: 0033:0x55b897ba0808 Code: (omitted) RSP: 002b:00007ffeefa821a0 EFLAGS: 00010287 RAX: 000055b89983acd0 RBX: 00007ffeefa823f8 RCX: 000055b89983acd0 RDX: 00007fc2f8122010 RSI: 0000000000020000 RDI: 000055b89983acd0 RBP: 00007ffeefa821a0 R08: 0000000000000037 R09: 0000000000000075 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000 R13: 00007ffeefa82410 R14: 000055b897ba5dd8 R15: 00007fc4b8340000 </TASK>
This sounds like we need a Fixes: and want to CC stable? -- Cheers, David / dhildenb
