Martin Zaharinov reports BUG() in mm land for 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 kvzallocGPF_ATOMIC). If kmalloc fails, this now
falls through to vmalloc and hits code paths that assume GFP_KERNEL.
Revert the problematic change and stay with slab allocator.
Reported-by: Martin Zaharinov <micron10@xxxxxxxxx>
Fixes: a421ef303008 ("mm: allow !GFP_KERNEL allocations for kvmalloc")
Cc: Michal Hocko <mhocko@xxxxxxxx>
Link: https://lore.kernel.org/netdev/09BE0B8A-3ADF-458E-B75E-931B74996355@xxxxxxxxx/T/#u
Signed-off-by: Florian Westphal <fw@xxxxxxxxx>
---
mm/util.c | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/mm/util.c b/mm/util.c
index c9439c66d8cf..ba7fe1cb6846 100644
--- a/mm/util.c
+++ b/mm/util.c
@@ -593,6 +593,13 @@ void *kvmalloc_node(size_t size, gfp_t flags, int node)
gfp_t kmalloc_flags = flags;
void *ret;
+ /*
+ * vmalloc uses GFP_KERNEL for some internal allocations (e.g page tables)
+ * so the given set of flags has to be compatible.
+ */
+ if ((flags & GFP_KERNEL) != GFP_KERNEL)
+ return kmalloc_node(size, flags, node);
+
/*
* We want to attempt a large physically contiguous block first because
* it is less likely to fragment multiple larger blocks and therefore
--
2.35.1
