The following commit has been merged into the objtool/urgent branch of tip: Commit-ID: f66c05d6baf36069c01a02f869bebb75586f2318 Gitweb: https://git.kernel.org/tip/f66c05d6baf36069c01a02f869bebb75586f2318 Author: Vasily Gorbik <gor@xxxxxxxxxxxxx> AuthorDate: Wed, 12 May 2021 19:42:13 +02:00 Committer: Ingo Molnar <mingo@xxxxxxxxxx> CommitterDate: Wed, 12 May 2021 21:17:01 +02:00 objtool/x86: Fix elf_add_alternative() endianness Currently x86 kernel cross-compiled on big endian system fails at boot with: kernel BUG at arch/x86/kernel/alternative.c:258! Corresponding bug condition look like the following: BUG_ON(feature >= (NCAPINTS + NBUGINTS) * 32); Fix that by converting alternative feature/cpuid to target endianness. Fixes: 9bc0bb50727c ("objtool/x86: Rewrite retpoline thunk calls") Signed-off-by: Vasily Gorbik <gor@xxxxxxxxxxxxx> Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> Acked-by: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx> Link: https://lore.kernel.org/r/patch-2.thread-6c9df9.git-6c9df9a8098d.your-ad-here.call-01620841104-ext-2554@work.hours --- tools/objtool/arch/x86/decode.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/tools/objtool/arch/x86/decode.c b/tools/objtool/arch/x86/decode.c index cedf3ed..24295d3 100644 --- a/tools/objtool/arch/x86/decode.c +++ b/tools/objtool/arch/x86/decode.c @@ -19,6 +19,7 @@ #include <objtool/elf.h> #include <objtool/arch.h> #include <objtool/warn.h> +#include <objtool/endianness.h> #include <arch/elf.h> static int is_x86_64(const struct elf *elf) @@ -725,7 +726,7 @@ static int elf_add_alternative(struct elf *elf, return -1; } - alt->cpuid = cpuid; + alt->cpuid = bswap_if_needed(cpuid); alt->instrlen = orig_len; alt->replacementlen = repl_len;