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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 8A68D21164 X-Spam-Level: X-Spamd-Result: default: False [-3.01 / 50.00]; BAYES_HAM(-3.00)[99.99%]; SUSPICIOUS_RECIPS(1.50)[]; NEURAL_HAM_LONG(-1.00)[-1.000]; R_DKIM_ALLOW(-0.20)[suse.cz:s=susede2_rsa,suse.cz:s=susede2_ed25519]; NEURAL_HAM_SHORT(-0.20)[-1.000]; MIME_GOOD(-0.10)[text/plain]; MX_GOOD(-0.01)[]; TO_MATCH_ENVRCPT_ALL(0.00)[]; FREEMAIL_ENVRCPT(0.00)[gmail.com]; DKIM_SIGNED(0.00)[suse.cz:s=susede2_rsa,suse.cz:s=susede2_ed25519]; FREEMAIL_CC(0.00)[kvack.org,vger.kernel.org,kernel.org,google.com,lge.com,linux-foundation.org,linux.dev,gmail.com]; ARC_NA(0.00)[]; FUZZY_BLOCKED(0.00)[rspamd.com]; RCVD_TLS_ALL(0.00)[]; DKIM_TRACE(0.00)[suse.cz:+]; RCVD_VIA_SMTP_AUTH(0.00)[]; RCVD_COUNT_TWO(0.00)[2]; FROM_EQ_ENVFROM(0.00)[]; FROM_HAS_DN(0.00)[]; MIME_TRACE(0.00)[0:+]; MID_RHS_MATCH_FROM(0.00)[]; RECEIVED_SPAMHAUS_BLOCKED_OPENRESOLVER(0.00)[2a07:de40:b281:106:10:150:64:167:received]; RCPT_COUNT_SEVEN(0.00)[10]; TAGGED_RCPT(0.00)[]; TO_DN_SOME(0.00)[] X-Rspamd-Server: rspamd2.dmz-prg2.suse.org X-Rspamd-Action: no action X-Spam-Score: -3.01 X-Spam-Flag: NO On 1/21/25 11:46, Kevin Brodsky wrote: > On 17/01/2025 23:13, Christoph Lameter (Ampere) wrote: >> On Fri, 17 Jan 2025, Kevin Brodsky wrote: >> >>> index a29457bef626..3b07cdaac3ae 100644 >>> --- a/mm/slab_common.c >>> +++ b/mm/slab_common.c >>> @@ -305,18 +305,6 @@ struct kmem_cache *__kmem_cache_create_args(const char *name, >>> goto out_unlock; >>> } >>> >>> - /* Refuse requests with allocator specific flags */ >>> - if (flags & ~SLAB_FLAGS_PERMITTED) { >>> - err = -EINVAL; >>> - goto out_unlock; >>> - } >> I think we should keep checking for invalid flags. > > The commit that introduced this check [1] aimed to ensure that no > allocator-specific flag is passed to kmem_cache_create(), so it seemed > to me it was no longer needed now that allocator-specific flags are gone. > > Having said that, we could keep it in order to reject flags that are not > supposed to be passed to kmem_cache_create() (e.g. SLAB_SKIP_KFENCE). > With that approach we'd just need to clear SLAB_DEBUG_FLAGS below if > !CONFIG_SLUB_DEBUG (and get rid of CACHE_CREATE_MASK). Sounds like a good plan to me, thanks! > - Kevin > > [1] > https://lore.kernel.org/all/1478553075-120242-2-git-send-email-thgarnie@google.com/ > >>> - /* >>> - * Some allocators will constraint the set of valid flags to a subset >>> - * of all flags. We expect them to define CACHE_CREATE_MASK in this >>> - * case, and we'll just provide them with a sanitized version of the >>> - * passed flags. >>> - */ >>> flags &= CACHE_CREATE_MASK; >> This would silently clear some flags instead of creating an error. > > >