+ selftests-mm-fix-warray-bounds-warnings-in-pkey_sighandler_tests-fix.patch added to mm-unstable branch

+ selftests-mm-fix-warray-bounds-warnings-in-pkey_sighandler_tests-fix.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: selftests-mm-fix-warray-bounds-warnings-in-pkey_sighandler_tests-fix
has been added to the -mm mm-unstable branch.  Its filename is
     selftests-mm-fix-warray-bounds-warnings-in-pkey_sighandler_tests-fix.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/selftests-mm-fix-warray-bounds-warnings-in-pkey_sighandler_tests-fix.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Kevin Brodsky <kevin.brodsky@arm.com>
Subject: selftests-mm-fix-warray-bounds-warnings-in-pkey_sighandler_tests-fix
Date: Wed, 18 Dec 2024 15:36:15 +0000

Dereferencing a null pointer on Clang is not a good idea - it will
entirely optimise out the dereference.  Make the pointer volatile to force
the access (and fault).

Link: https://lkml.kernel.org/r/20241218153615.2267571-1-kevin.brodsky@arm.com
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202412140850.4TW4YBqc-lkp@intel.com/
Signed-off-by: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Aruna Ramakrishna <aruna.ramakrishna@oracle.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Joey Gouly <joey.gouly@arm.com>
Cc: Keith Lucas <keith.lucas@oracle.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 tools/testing/selftests/mm/pkey_sighandler_tests.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/tools/testing/selftests/mm/pkey_sighandler_tests.c~selftests-mm-fix-warray-bounds-warnings-in-pkey_sighandler_tests-fix
+++ a/tools/testing/selftests/mm/pkey_sighandler_tests.c
@@ -163,7 +163,7 @@ static void *thread_segv_with_pkey0_disa
 	__write_pkey_reg(pkey_reg_restrictive_default());
 
 	/* Segfault (with SEGV_MAPERR) */
-	*(int *)NULL = 1;
+	*(volatile int *)NULL = 1;
 	return NULL;
 }
 
@@ -194,7 +194,7 @@ static void *thread_segv_maperr_ptr(void
 	__write_pkey_reg(pkey_reg);
 
 	/* Segfault */
-	*(int *)NULL = 1;
+	*(volatile int *)NULL = 1;
 	syscall_raw(SYS_exit, 0, 0, 0, 0, 0, 0);
 	return NULL;
 }
_

Patches currently in -mm which might be from kevin.brodsky@arm.com are

selftests-mm-fix-condition-in-uffd_move_test_common.patch
selftests-mm-fix-wmaybe-uninitialized-warnings.patch
selftests-mm-fix-strncpy-length.patch
selftests-mm-fix-warray-bounds-warnings-in-pkey_sighandler_tests.patch
selftests-mm-fix-warray-bounds-warnings-in-pkey_sighandler_tests-fix.patch
selftests-mm-build-with-o2.patch
selftests-mm-remove-unused-pkey-helpers.patch
selftests-mm-define-types-using-typedef-in-pkey-helpersh.patch
selftests-mm-ensure-pkey-h-define-inline-functions-only.patch
selftests-mm-remove-empty-pkey-helper-definition.patch
selftests-mm-ensure-non-global-pkey-symbols-are-marked-static.patch
selftests-mm-use-sys_pkey-helpers-consistently.patch
selftests-mm-use-sys_pkey-helpers-consistently-fix.patch
selftests-mm-rename-pkey-register-macro.patch
selftests-mm-skip-pkey_sighandler_tests-if-support-is-missing.patch
selftests-mm-remove-x-permission-from-sigaltstack-mapping.patch