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author | Maria Matejka <mq@ucw.cz> | 2023-05-05 09:39:13 +0200 |
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committer | Maria Matejka <mq@ucw.cz> | 2023-05-06 10:50:32 +0200 |
commit | a95141111c89803347c36501185a76fc73a9764a (patch) | |
tree | a96a54914cf2498d02546ed49f8e2b852680229b /sysdep/bsd/sysio.h | |
parent | 00f30ac40bda76b289b1dc5c5aa8a5d2e4941985 (diff) |
Fixed a bug in hot page global storage
The original algorithm was suffering from an ABA race condition:
A: fp = page_stack
B: completely allocates the same page and writes into it some data
A: unsuspecting, loads (invalid) next = fp->next
B: finishes working with the page and returns it back to page_stack
A: compare-exchange page_stack: fp => next succeeds and writes garbage
to page_stack
Fixed this by using an implicit spinlock in hot page allocator.
Diffstat (limited to 'sysdep/bsd/sysio.h')
0 files changed, 0 insertions, 0 deletions