Avoid possible deadlock while locking multiple heap pages.
To avoid deadlock, backend acquires a lock on heap pages in block
number order. In certain cases, lock on heap pages is dropped and
reacquired. In this case, the locks are dropped for reading in
corresponding VM page/s. The issue is we re-acquire locks in bufferId
order whereas the intention was to acquire in blockid order.
This commit ensures that we will always acquire locks on heap pages in
blockid order.
Reported-by: Nishant Fnu
Author: Nishant Fnu
Reviewed-by: Amit Kapila and Robert Haas
Backpatch-through: 9.4
Discussion: https://postgr.es/m/5883C831-2ED1-47C8-BFAC-2D5BAE5A8CAE@amazon.com
Branch
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REL_11_STABLE
Details
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https://git.postgresql.org/pg/commitdiff/904413637f8b04aab02cbe03173a1a0bdadc2b6b
Modified Files
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src/backend/access/heap/hio.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)