arm64: entry: Remove confusing comment

The comment about SYS_MEMBARRIER_SYNC_CORE relying on ERET being
context-synchronizing is confusing and misplaced with kpti. Given that
this is already documented under Documentation/ (see arch-support.txt
for membarrier), remove the comment altogether.

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

diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S
index a7fc77ab4a0ac50d681b45bb7896e448a3239fac..c7d050207e5388b4a28bf6f6e762db8da958f5e1 100644 (file)
--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -344,10 +344,6 @@ alternative_else_nop_endif
        ldp     x28, x29, [sp, #16 * 14]
        ldr     lr, [sp, #S_LR]
        add     sp, sp, #S_FRAME_SIZE           // restore sp
-       /*
-        * ARCH_HAS_MEMBARRIER_SYNC_CORE rely on eret context synchronization
-        * when returning from IPI handler, and when returning to user-space.
-        */
 
        .if     \el == 0
 alternative_insn eret, nop, ARM64_UNMAP_KERNEL_AT_EL0