This reverts commit ac7c3e4ff401b304489a031938dbeaab585bfe0a for ARM and arm64.
Building an arm64 kernel with CONFIG_OPTIMIZE_INLINING=y has been shown to violate fixed register allocations of local variables passed to inline assembly with GCC prior to version 9 which can lead to subtle failures at runtime: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91111 A very similar has been reported for 32-bit ARM as well: https://lkml.kernel.org/r/[email protected] Although GCC 9.1 appears to work for the specific case in the bugzilla above, the exact issue has not been root-caused so play safe and disable the option for now on these architectures. Cc: Nicolas Saenz Julienne <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Russell King <[email protected]> Cc: Masahiro Yamada <[email protected]>, Cc: Arnd Bergmann <[email protected]> Signed-off-by: Will Deacon <[email protected]> --- lib/Kconfig.debug | 1 + 1 file changed, 1 insertion(+) diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 93d97f9b0157..c37c72adaeff 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -312,6 +312,7 @@ config HEADERS_CHECK config OPTIMIZE_INLINING def_bool y + depends on !(ARM || ARM64) # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91111 help This option determines if the kernel forces gcc to inline the functions developers have marked 'inline'. Doing so takes away freedom from gcc to -- 2.23.0.444.g18eeb5a265-goog
