acca4f4d9b
There was a race in the kmap_coherent() implementation. While we
guarded against preemption, there was nothing preventing eviction of
the pre-faulted fixmap entry from the UTLB. Under certain workloads
this would result in the fixmap entries used for cache colouring being
evicted from the UTLB in the midst of a copy_page().
In addition to pre-faulting, we also make sure to preserve the PTEs
in the kernel page table and introduce a cached PTE for kmap_coherent()
usage. This follows a similar change on MIPS ("[MIPS] Fix aliasing bug
in copy_to_user_page / copy_from_user_page").
Reported-by: Hideo Saito <saito@densan.co.jp>
Reported-by: CHIKAMA Masaki <masaki.chikama@gmail.com>
Tested-by: Yoshihiro Shimoda <shimoda.yoshihiro@renesas.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
|
||
|---|---|---|
| .. | ||
| asm | ||
| cpu-common/cpu | ||
| cpu-sh2/cpu | ||
| cpu-sh2a/cpu | ||
| cpu-sh3/cpu | ||
| cpu-sh4/cpu | ||
| cpu-sh5/cpu | ||
| mach-common/mach | ||
| mach-dreamcast/mach | ||
| mach-landisk/mach | ||
| mach-se/mach | ||
| mach-sh03/mach | ||