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charset=us-ascii Content-Disposition: inline In-Reply-To: On Mon, Oct 21, 2024 at 10:42:02AM +0200, Vlastimil Babka wrote: > On 10/19/24 02:02, Dominique Martinet wrote: > > Vlastimil Babka wrote on Fri, Oct 18, 2024 at 11:38:04PM +0200: > >> > In that case: Linus, given the circumstances I wonder if it would be > >> > best if you could merge the patch at the start of this thread > >> > (https://lore.kernel.org/all/20240807094725.2193423-1-pedro.falcato@gmail.com/ > >> > ) directly, which can also be found as 79efebae4afc22 in -next if you > >> > prefer to cherry-pick it from there Either now or after 24 to 36 hours, > >> > which would give Eric a chance to ACK/NACK this if he sees this mail. > > > > Sorry to everyone involved, I've just sent the merge request - I wasn't > > much at computer in the past few weeks so wanted to wait until I got > > back home to send it just in case, as I didn't realize this was a recent > > regression that caused actual harm (it sounded like an old warning that > > someone just recently happened to hit, and sounded easy enough to work > > around locally if there is only one specific setup involved); I should > > have sent the fix separately or at least corrected myself about the > > schedule. > > > >> >>> It is causing regressions in my environment > >> >>> #regzbot introduced: 4c39529663b9 > >> > > >> > If anyone wonders, that is 4c39529663b931 ("slab: Warn on duplicate > >> > cache names when DEBUG_VM=y") [v6.12-rc1]. That's also why I'm CCing > >> > Vlastimil, so he knows about this. > > > > (that might have been nice to have as a Fixes tag for eventual backport, > > but at least that commit doesn't appear to have been picked up by stable > > so it's probably fine as is) > > Yeah it's missing the tag because I believe Pedro sent the 9p fix before > sending the new warning patch itself, so there was even no commit ID yet. > The plan was to introduce the warning only after all pre-existing in-tree > code that would triggers it was fixed. I just assumed the fix would be > mainlined before/at the same time as the warning itself, but forgot to > check. In any case if I see e.g. autosel picking the warning patch for > stable, I'll object. > > Thanks, > Vlastimil FYI, drgn's CI started getting EIO errors from getdents("/sys/kernel/slab") that I bisected to this patch. The problem is that dev_name can be an arbitrary string. In my case, it is "/dev/root". This trips verify_dirent_name(), which fails if a filename contains a slash. This needs to use a different unique identifier. Maybe clnt->msize? But then the kmem_caches will need to be shared between different mounts using the same msize. In any case, can this be reverted for now? Thanks, Omar