On Wed, Dec 4, 2024 at 11:25 AM Matthew Wilcox <willy@xxxxxxxxxxxxx> wrote: > > On Wed, Dec 04, 2024 at 09:17:27AM -0700, Jens Axboe wrote: > > > XA_STATE(xas, xa, index); > > > - return xas_result(&xas, xas_store(&xas, NULL)); > > > + return xas_result(&xas, xa_zero_to_null(xas_store(&xas, NULL))); > > > } > > > EXPORT_SYMBOL(__xa_erase); > > > > > > This would explain deletion of a reserved entry returning > > > `XA_ZERO_ENTRY` rather than `NULL`. > > > > Yep this works. > > > > > My apologies for this breakage. Should I send a new version? A new > > > "fixes" patch? > > > > Since it seems quite drastically broken, and since it looks like Andrew > > is holding it, seems like the best course of action would be to have it > > folded with the existing patch. > > ... and please include an addition to the test-suite that would catch > this bug. > > Wait, why doesn't this one catch it? You did run the test-suite, right? > > /* xa_insert treats it as busy */ > XA_BUG_ON(xa, xa_reserve(xa, 12345678, GFP_KERNEL) != 0); > XA_BUG_ON(xa, xa_insert(xa, 12345678, xa_mk_value(12345678), 0) != > -EBUSY); > XA_BUG_ON(xa, xa_empty(xa)); > XA_BUG_ON(xa, xa_erase(xa, 12345678) != NULL); > XA_BUG_ON(xa, !xa_empty(xa)); I thought I did, but when I ran it again just now, this test did catch it. So there is coverage.
