diff options
| author | robin.kuo <robin.kuo@mediatek.com> | 2026-01-16 14:25:00 +0800 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2026-01-26 19:03:45 -0800 |
| commit | a0f3c0845a4ff68d403c568266d17e9cc553e561 (patch) | |
| tree | f3393d2a02e850f85d019e193faa113069d363b4 /mm | |
| parent | 9b47d4eea3f7c1f620e95bda1d6221660bde7d7b (diff) | |
mm, swap: restore swap_space attr aviod kernel panic
commit 8b47299a411a ("mm, swap: mark swap address space ro and add context
debug check") made the swap address space read-only. It may lead to
kernel panic if arch_prepare_to_swap returns a failure under heavy memory
pressure as follows,
el1_abort+0x40/0x64
el1h_64_sync_handler+0x48/0xcc
el1h_64_sync+0x84/0x88
errseq_set+0x4c/0xb8 (P)
__filemap_set_wb_err+0x20/0xd0
shrink_folio_list+0xc20/0x11cc
evict_folios+0x1520/0x1be4
try_to_shrink_lruvec+0x27c/0x3dc
shrink_one+0x9c/0x228
shrink_node+0xb3c/0xeac
do_try_to_free_pages+0x170/0x4f0
try_to_free_pages+0x334/0x534
__alloc_pages_direct_reclaim+0x90/0x158
__alloc_pages_slowpath+0x334/0x588
__alloc_frozen_pages_noprof+0x224/0x2fc
__folio_alloc_noprof+0x14/0x64
vma_alloc_zeroed_movable_folio+0x34/0x44
do_pte_missing+0xad4/0x1040
handle_mm_fault+0x4a4/0x790
do_page_fault+0x288/0x5f8
do_translation_fault+0x38/0x54
do_mem_abort+0x54/0xa8
Restore swap address space as not ro to avoid the panic.
Link: https://lkml.kernel.org/r/20260116062535.306453-2-robin.kuo@mediatek.com
Fixes: 8b47299a411a ("mm, swap: mark swap address space ro and add context debug check")
Signed-off-by: robin.kuo <robin.kuo@mediatek.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: andrew.yang <andrew.yang@mediatek.com>
Cc: AngeloGiaocchino Del Regno <angelogioacchino.delregno@collabora.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Chinwen Chang <chinwen.chang@mediatek.com>
Cc: Chris Li <chrisl@kernel.org>
Cc: Kairui Song <kasong@tencent.com>
Cc: Kairui Song <ryncsn@gmail.com>
Cc: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: Mathias Brugger <matthias.bgg@gmail.com>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Qun-wei Lin <Qun-wei.Lin@mediatek.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/swap.h | 2 | ||||
| -rw-r--r-- | mm/swap_state.c | 3 |
2 files changed, 2 insertions, 3 deletions
diff --git a/mm/swap.h b/mm/swap.h index d034c13d8dd2..1bd466da3039 100644 --- a/mm/swap.h +++ b/mm/swap.h @@ -198,7 +198,7 @@ int swap_writeout(struct folio *folio, struct swap_iocb **swap_plug); void __swap_writepage(struct folio *folio, struct swap_iocb **swap_plug); /* linux/mm/swap_state.c */ -extern struct address_space swap_space __ro_after_init; +extern struct address_space swap_space __read_mostly; static inline struct address_space *swap_address_space(swp_entry_t entry) { return &swap_space; diff --git a/mm/swap_state.c b/mm/swap_state.c index 5f97c6ae70a2..44d228982521 100644 --- a/mm/swap_state.c +++ b/mm/swap_state.c @@ -37,8 +37,7 @@ static const struct address_space_operations swap_aops = { #endif }; -/* Set swap_space as read only as swap cache is handled by swap table */ -struct address_space swap_space __ro_after_init = { +struct address_space swap_space __read_mostly = { .a_ops = &swap_aops, }; |