arm64: Enable CONFIG_COMPAT also for 64k page size

With binutils 2.25 the default alignment for 32bit arm sections changed to
have everything 64k aligned. Armv7 binaries built with this binutils version
run successfully on an arm64 system.

Since effectively there is now the chance to run armv7 code on arm64 even
with 64k page size, it doesn't make sense to block people from enabling
CONFIG_COMPAT on those configurations.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Will Deacon <will.deacon@arm.com>

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 0d46debbc9a7d0a5f5fbd07082d7a717a261c977..c102d92aad4076a4996d1519c8318c7c1effb3df 100644 (file)
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -674,7 +674,7 @@ source "fs/Kconfig.binfmt"
 
 config COMPAT
        bool "Kernel support for 32-bit EL0"
-       depends on !ARM64_64K_PAGES
+       depends on !ARM64_64K_PAGES || EXPERT
        select COMPAT_BINFMT_ELF
        select HAVE_UID16
        select OLD_SIGSUSPEND3
@@ -685,6 +685,10 @@ config COMPAT
          the user helper functions, VFP support and the ptrace interface are
          handled appropriately by the kernel.
 
+         If you also enabled CONFIG_ARM64_64K_PAGES, please be aware that you
+         will only be able to execute AArch32 binaries that were compiled with
+         64k aligned segments.
+
          If you want to execute 32-bit userspace applications, say Y.
 
 config SYSVIPC_COMPAT