mirror of
https://github.com/torvalds/linux.git
synced 2024-11-29 23:51:37 +00:00
1d094cefc3
The watchpoint encoding masks for size and address were off-by-one bit each, with the size mask using 1 unnecessary bit and the address mask missing 1 bit. However, due to the way the size is shifted into the encoded watchpoint, we were effectively wasting and never using the extra bit. For example, on x86 with PAGE_SIZE==4K, we have 1 bit for the is-write bit, 14 bits for the size bits, and then 49 bits left for the address. Prior to this fix we would end up with this usage: [ write<1> | size<14> | wasted<1> | address<48> ] Fix it by subtracting 1 bit from the GENMASK() end and start ranges of size and address respectively. The added static_assert()s verify that the masks are as expected. With the fixed version, we get the expected usage: [ write<1> | size<14> | address<49> ] Functionally no change is expected, since that extra address bit is insignificant for enabled architectures. Acked-by: Boqun Feng <boqun.feng@gmail.com> Signed-off-by: Marco Elver <elver@google.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org> |
||
|---|---|---|
| .. | ||
| atomic.h | ||
| core.c | ||
| debugfs.c | ||
| encoding.h | ||
| kcsan-test.c | ||
| kcsan.h | ||
| Makefile | ||
| report.c | ||
| selftest.c | ||