The patch titled Subject: mm: fix BUG splat with kvmalloc + GFP_ATOMIC has been added to the -mm mm-hotfixes-unstable branch. Its filename is mm-fix-bug-splat-with-kvmalloc-gfp_atomic.patch

This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches...

This patch will later appear in the mm-hotfixes-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------ From: Florian Westphal fw@strlen.de Subject: mm: fix BUG splat with kvmalloc + GFP_ATOMIC Date: Mon, 26 Sep 2022 17:16:50 +0200

Martin Zaharinov reports BUG with 5.19.10 kernel: kernel BUG at mm/vmalloc.c:2437! invalid opcode: 0000 [#1] SMP CPU: 28 PID: 0 Comm: swapper/28 Tainted: G W O 5.19.9 #1 [..] RIP: 0010:__get_vm_area_node+0x120/0x130 __vmalloc_node_range+0x96/0x1e0 kvmalloc_node+0x92/0xb0 bucket_table_alloc.isra.0+0x47/0x140 rhashtable_try_insert+0x3a4/0x440 rhashtable_insert_slow+0x1b/0x30 [..]

bucket_table_alloc uses kvzalloc(GPF_ATOMIC). If kmalloc fails, this now falls through to vmalloc and hits code paths that assume GFP_KERNEL.

Link: https://lkml.kernel.org/r/20220926151650.15293-1-fw@strlen.de Fixes: a421ef303008 ("mm: allow !GFP_KERNEL allocations for kvmalloc") Signed-off-by: Florian Westphal fw@strlen.de Suggested-by: Michal Hocko mhocko@suse.com Link: https://lore.kernel.org/linux-mm/Yy3MS2uhSgjF47dy@pc636/T/#t Acked-by: Michal Hocko mhocko@suse.com Reported-by: Martin Zaharinov micron10@gmail.com Cc: Uladzislau Rezki (Sony) urezki@gmail.com Cc: Vlastimil Babka vbabka@suse.cz Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org ---

--- a/mm/util.c~mm-fix-bug-splat-with-kvmalloc-gfp_atomic +++ a/mm/util.c @@ -619,6 +619,10 @@ void *kvmalloc_node(size_t size, gfp_t f if (ret || size <= PAGE_SIZE) return ret;

+ /* non-sleeping allocations are not supported by vmalloc */ + if (!gfpflags_allow_blocking(flags)) + return NULL; + /* Don't even allow crazy sizes */ if (unlikely(size > INT_MAX)) { WARN_ON_ONCE(!(flags & __GFP_NOWARN)); _

Patches currently in -mm which might be from fw@strlen.de are

mm-fix-bug-splat-with-kvmalloc-gfp_atomic.patch