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charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Stat-Signature: 7h46dunw7ny1f6nsq7fkc7rhnwe1g853 X-Rspamd-Queue-Id: A7687180009 X-Rspam-User: X-Rspamd-Server: rspam08 X-HE-Tag: 1721372865-781298 X-HE-Meta: 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 XEkdnn0d ezaGkFJiWdA556SK6LCLn1K7/WkWIWnIyLTWBzmP9WKfw6DLgVd7KESPUEaoJ3JASeRrQNJA6hjvzxeUEE3siaaV3R9t5NqhNwhaeSmrtNTW9gOIOEYBwnwfNqVcATW7d1cttCO5Or/E4CfC5MTBSIR7vfP5tbPDpfpXi8Istzr7ZWVDmEUzpXauOkVBfUBwCmvWhffGjy8MihRELM0hyDxVs7AYgoQxvCFq69Pv8eqkuB3peFLFv5TSd3AhIuzTfGfCjFEsXYfPrNpMO0lNbH+5Q6rAluzFpvH9u0RqF5r4fBpTgzQ5056TV/jZjAuddvea8WGR51Qf3Y1vvlmtDHqcEvY0Uw/uiQqcJ3hsLBMSoOn/tgdhL0dmopmHFzEU/lsgtiGEblgL1yY+TPsVFjibC9HfhF+yIXtGIDlTpkV4jDibDGRBKmc6QS4DpbYnUTtbJAE7NdFCCdqr2Ug/KsewM1UAsY8znXAVf 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: List-Subscribe: List-Unsubscribe: On Fri, Jul 19, 2024 at 7:02=E2=80=AFPM Michal Hocko wrot= e: > > On Fri 19-07-24 12:35:55, Barry Song wrote: > > On Thu, Jul 18, 2024 at 8:50=E2=80=AFPM Michal Hocko = wrote: > [...] > > > Yes, those shouldn't really fail. NOWAIT|NOFAIL was something that > > > should never happen and I really hope it doesn't. Others should reall= y > > > retry but it's been some time since I've checked the last time. > > > > > > I assume allocations directly using alloc_pages() might not respect GFP= _NOFAIL > > and violate the semantics of GFP_NOFAIL. > > What do you mean? I mean, if we are using wrappers like vmalloc (GFP_NOFAIL | GFP_NOWAIT), though alloc_pages might return NULL, vmalloc for itself will retry. but if you call alloc_pages() directly with GFP_NOFAIL | GFP_NOWAIT, alloc_pages() may return NULL without retry at all. I believe alloc_pages() is also wrong. > > > Additionally, at least drivers/vdpa/vdpa_user/iova_domain.c is > > incorrect with GFP_ATOMIC > > | __GFP_NOFAIL. > > This is broken! Please bring this up with the maintainer of the code. > > [...] > > > GFP_NOFAIL things need to be fixed. Let me investigate further. > > Thanks! > > -- > Michal Hocko > SUSE Labs