Will Deacon 04b8637be9 arm64: alternatives: ensure secondary CPUs execute ISB after patching ...

In order to guarantee that the patched instruction stream is visible to
a CPU, that CPU must execute an isb instruction after any related cache
maintenance has completed.

The instruction patching routines in kernel/insn.c get this right for
things like jump labels and ftrace, but the alternatives patching omits
it entirely leaving secondary cores in a potential limbo between the old
and the new code.

This patch adds an isb following the secondary polling loop in the
altenatives patching.

Signed-off-by: Will Deacon <will.deacon@arm.com>

2015-08-04 18:52:09 +01:00

4.0 KiB

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