diff options
| author | Fuad Tabba <tabba@google.com> | 2021-05-24 11:29:48 +0300 |
|---|---|---|
| committer | Will Deacon <will@kernel.org> | 2021-05-25 21:27:48 +0300 |
| commit | 7908072da535dca52b3a011ed6e1f73534546b59 (patch) | |
| tree | eb5496c42293868a8f25e32264495a2e0e612ff9 /arch/arm64/mm/cache.S | |
| parent | 116b7f559492b719ae4bd22ee773cb7fb046a736 (diff) | |
| download | linux-7908072da535dca52b3a011ed6e1f73534546b59.tar.xz | |
arm64: Do not enable uaccess for invalidate_icache_range
invalidate_icache_range() works on kernel addresses, and doesn't
need uaccess. Remove the code that toggles uaccess_ttbr0_enable,
as well as the code that emits an entry into the exception table
(via the macro invalidate_icache_by_line).
Changes return type of invalidate_icache_range() from int (which
used to indicate a fault) to void, since it doesn't need uaccess
and won't fault. Note that return value was never checked by any
of the callers.
No functional change intended.
Possible performance impact due to the reduced number of
instructions.
Reported-by: Catalin Marinas <catalin.marinas@arm.com>
Reported-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/linux-arch/20200511110014.lb9PEahJ4hVOYrbwIb_qUHXyNy9KQzNFdb_I3YlzY6A@z/
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Fuad Tabba <tabba@google.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20210524083001.2586635-6-tabba@google.com
Signed-off-by: Will Deacon <will@kernel.org>
Diffstat (limited to 'arch/arm64/mm/cache.S')
| -rw-r--r-- | arch/arm64/mm/cache.S | 11 |
1 files changed, 1 insertions, 10 deletions
diff --git a/arch/arm64/mm/cache.S b/arch/arm64/mm/cache.S index 7c54bcbf5a36..14eac9d76d57 100644 --- a/arch/arm64/mm/cache.S +++ b/arch/arm64/mm/cache.S @@ -90,21 +90,12 @@ SYM_FUNC_END(__flush_cache_user_range) */ SYM_FUNC_START(invalidate_icache_range) alternative_if ARM64_HAS_CACHE_DIC - mov x0, xzr isb ret alternative_else_nop_endif - uaccess_ttbr0_enable x2, x3, x4 - - invalidate_icache_by_line x0, x1, x2, x3, 2f - mov x0, xzr -1: - uaccess_ttbr0_disable x1, x2 + invalidate_icache_by_line x0, x1, x2, x3 ret -2: - mov x0, #-EFAULT - b 1b SYM_FUNC_END(invalidate_icache_range) /* |