On 31.12.2020 22:03, Ryan Libby wrote:
The branch main has been updated by rlibby:
URL:
https://cgit.FreeBSD.org/src/commit/?id=942951ba46ecd5ebab18de006a24dc52e2d3f745
commit 942951ba46ecd5ebab18de006a24dc52e2d3f745
Author: Ryan Libby <rli...@freebsd.org>
AuthorDate: 2020-12-31 21:02:45 +0000
Commit: Ryan Libby <rli...@freebsd.org>
CommitDate: 2020-12-31 21:02:45 +0000
uma dbg: catch more corruption with atomics
Use atomic testandset and testandclear to catch concurrent double free,
and to reduce the number of atomic operations.
Submitted by: jeff
Reviewed by: cem, kib, markj (all previous version)
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D22703
Unfortunately, this broke arm and arm64 kernel with random
'duplicate alloc'/'duplicate free' panics.
Michal
---
sys/vm/uma_core.c | 9 ++++-----
1 file changed, 4 insertions(+), 5 deletions(-)
diff --git a/sys/vm/uma_core.c b/sys/vm/uma_core.c
index a0192642205d..39c846effac8 100644
--- a/sys/vm/uma_core.c
+++ b/sys/vm/uma_core.c
@@ -5392,10 +5392,10 @@ uma_dbg_alloc(uma_zone_t zone, uma_slab_t slab, void
*item)
keg = zone->uz_keg;
freei = slab_item_index(slab, keg, item);
- if (BIT_ISSET(keg->uk_ipers, freei, slab_dbg_bits(slab, keg)))
+ if (BIT_TEST_SET_ATOMIC(keg->uk_ipers, freei,
+ slab_dbg_bits(slab, keg)))
panic("Duplicate alloc of %p from zone %p(%s) slab %p(%d)",
item, zone, zone->uz_name, slab, freei);
- BIT_SET_ATOMIC(keg->uk_ipers, freei, slab_dbg_bits(slab, keg));
}
/*
@@ -5426,11 +5426,10 @@ uma_dbg_free(uma_zone_t zone, uma_slab_t slab, void
*item)
panic("Unaligned free of %p from zone %p(%s) slab %p(%d)",
item, zone, zone->uz_name, slab, freei);
- if (!BIT_ISSET(keg->uk_ipers, freei, slab_dbg_bits(slab, keg)))
+ if (!BIT_TEST_CLR_ATOMIC(keg->uk_ipers, freei,
+ slab_dbg_bits(slab, keg)))
panic("Duplicate free of %p from zone %p(%s) slab %p(%d)",
item, zone, zone->uz_name, slab, freei);
-
- BIT_CLR_ATOMIC(keg->uk_ipers, freei, slab_dbg_bits(slab, keg));
}
#endif /* INVARIANTS */
_______________________________________________
dev-commits-src-main@freebsd.org mailing list
https://lists.freebsd.org/mailman/listinfo/dev-commits-src-main
To unsubscribe, send any mail to "dev-commits-src-main-unsubscr...@freebsd.org"
