Re: [PATCH] mm/memtest: Add ARCH_USE_MEMTEST

On Thu, Feb 4, 2021 at 8:10 PM Anshuman Khandual
[off-list ref] wrote:

early_memtest() does not get called from all architectures. Hence enabling
CONFIG_MEMTEST and providing a valid memtest=[1..N] kernel command line
option might not trigger the memory pattern tests as would be expected in
normal circumstances. This situation is misleading.

The change here prevents the above mentioned problem after introducing a
new config option ARCH_USE_MEMTEST that should be subscribed on platforms
that call early_memtest(), in order to enable the config CONFIG_MEMTEST.
Conversely CONFIG_MEMTEST cannot be enabled on platforms where it would
not be tested anyway.

Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <redacted>
Cc: Thomas Gleixner <redacted>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-mips@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-xtensa@linux-xtensa.org
Cc: linux-mm@kvack.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Anshuman Khandual <redacted>
---
This patch applies on v5.11-rc6 and has been tested on arm64 platform. But
it has been just build tested on all other platforms.

 arch/arm/Kconfig     | 1 +
 arch/arm64/Kconfig   | 1 +
 arch/mips/Kconfig    | 1 +
 arch/powerpc/Kconfig | 1 +
 arch/x86/Kconfig     | 1 +
 arch/xtensa/Kconfig  | 1 +
 lib/Kconfig.debug    | 9 ++++++++-
 7 files changed, 14 insertions(+), 1 deletion(-)

Anshuman, entries in arch/*/Konfig files are sorted in alphabetical order,
please keep them that way.

Reviewed-by: Max Filippov <jcmvbkbc@gmail.com>

-- 
Thanks.
-- Max