aboutsummaryrefslogtreecommitdiff
path: root/Documentation/userspace-api
diff options
context:
space:
mode:
authorYandong Zhao2018-07-11 19:06:28 +0800
committerWill Deacon2018-07-11 17:02:02 +0100
commit2fd8eb4ad87104c54800ef3cea498c92eb15c78a (patch)
treeba0d6cb6f9dee0872b801d0d021e8ae84382e1b5 /Documentation/userspace-api
parent96f95a17c1cfe65a002e525114d96616e91a8f2d (diff)
arm64: neon: Fix function may_use_simd() return error status
It does not matter if the caller of may_use_simd() migrates to another cpu after the call, but it is still important that the kernel_neon_busy percpu instance that is read matches the cpu the task is running on at the time of the read. This means that raw_cpu_read() is not sufficient. kernel_neon_busy may appear true if the caller migrates during the execution of raw_cpu_read() and the next task to be scheduled in on the initial cpu calls kernel_neon_begin(). This patch replaces raw_cpu_read() with this_cpu_read() to protect against this race. Cc: <stable@vger.kernel.org> Fixes: cb84d11e1625 ("arm64: neon: Remove support for nested or hardirq kernel-mode NEON") Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Yandong Zhao <yandong77520@gmail.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
Diffstat (limited to 'Documentation/userspace-api')
0 files changed, 0 insertions, 0 deletions