+ arm64-entry-use-stackleak_erase_on_task_stack.patch added to -mm tree

[Andrew Morton <akpm@linux-foundation.org>]

The patch titled
     Subject: arm64: entry: use stackleak_erase_on_task_stack()
has been added to the -mm tree.  Its filename is
     arm64-entry-use-stackleak_erase_on_task_stack.patch

This patch should soon appear at
    https://ozlabs.org/~akpm/mmots/broken-out/arm64-entry-use-stackleak_erase_on_task_stack.patch
and later at
    https://ozlabs.org/~akpm/mmotm/broken-out/arm64-entry-use-stackleak_erase_on_task_stack.patch

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------------------------------------------------------
From: Mark Rutland <mark.rutland@arm.com>
Subject: arm64: entry: use stackleak_erase_on_task_stack()

On arm64 we always call stackleak_erase() on a task stack, and never call
it on another stack.  We can avoid some redundant work by using
stackleak_erase_on_task_stack(), telling the stackleak code that it's
being called on a task stack.

Link: https://lkml.kernel.org/r/20220425115603.781311-9-mark.rutland@arm.com
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Alexander Popov <alex.popov@linux.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 arch/arm64/kernel/entry.S |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/arm64/kernel/entry.S~arm64-entry-use-stackleak_erase_on_task_stack
+++ a/arch/arm64/kernel/entry.S
@@ -596,7 +596,7 @@ SYM_CODE_START_LOCAL(ret_to_user)
 	ldr	x19, [tsk, #TSK_TI_FLAGS]	// re-check for single-step
 	enable_step_tsk x19, x2
 #ifdef CONFIG_GCC_PLUGIN_STACKLEAK
-	bl	stackleak_erase
+	bl	stackleak_erase_on_task_stack
 #endif
 	kernel_exit 0
 SYM_CODE_END(ret_to_user)
_

Patches currently in -mm which might be from mark.rutland@arm.com are

arm64-stackleak-fix-current_top_of_stack.patch
stackleak-move-skip_erasing-check-earlier.patch
stackleak-rework-stack-low-bound-handling.patch
stackleak-clarify-variable-names.patch
stackleak-rework-stack-high-bound-handling.patch
stackleak-remove-redundant-check.patch
stackleak-add-on-off-stack-variants.patch
arm64-entry-use-stackleak_erase_on_task_stack.patch