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See http://www.infradead.org/rpr.html X-Rspam-User: X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 7B7371C000F X-Stat-Signature: 97jpm75osi1dtkr1uenp9x8rgfc947wt X-HE-Tag: 1671699026-74672 X-HE-Meta: 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 gKBzCUBp PPWVqqp9/33VafQCBNKf047+7yzx3dYiwWXVzK/IOr4twVB3TUWvdam+DKCn6zODincCFKVKoVZezFOcc3H1w0K/ks3xmV/JsH5mW6G1z4fG3BmIt/zuTjDGGGuA5Ma49DCDmTkkP3SanIy2hlHWzYFL8JTXWzKvK23tGZ15a4FLilikOLGkz6r0Y8w== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Looks good: Reviewed-by: Christoph Hellwig On Wed, Dec 21, 2022 at 06:44:53PM +0100, Uladzislau Rezki (Sony) wrote: > Switch from find_vmap_area() to find_unlink_vmap_area() to prevent > a double access to the vmap_area_lock: one for finding area, second > time is for unlinking from a tree. > > Signed-off-by: Uladzislau Rezki (Sony) > --- > mm/vmalloc.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/mm/vmalloc.c b/mm/vmalloc.c > index 28030d2441f1..17e688cc7357 100644 > --- a/mm/vmalloc.c > +++ b/mm/vmalloc.c > @@ -2251,7 +2251,7 @@ void vm_unmap_ram(const void *mem, unsigned int count) > return; > } > > - va = find_vmap_area(addr); > + va = find_unlink_vmap_area(addr); I can't find find_unlink_vmap_area in current -next, but shouldn't this also switch from free_vmap_area_noflush to something that doesn't unlink from the list and avoid the lock? In general the code could probably use a bit of refactoring to split unmapping from freeing.