On Fri 23-09-22 15:35:12, Florian Westphal wrote: > Michal Hocko <mhocko@xxxxxxxx> wrote: > > On Fri 23-09-22 12:38:58, Florian Westphal wrote: > > > 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. > > > > Why don't you simply fix the caller? > > Uh, not following? > > kvzalloc(GFP_ATOMIC) was perfectly fine, is this illegal again? kvmalloc has never really supported GFP_ATOMIC semantic. > I can revert 93f976b5190df32793908d49165f78e67fcb66cf instead > but that change is from 2018. Yeah I would just revert this one as it relies on internal details of kvmalloc doing or not doing a fallback. -- Michal Hocko SUSE Labs