[PATCH 5.10 02/77] ARM: 9133/1: mm: proc-macros: ensure *_tlb_fns are 4B aligned

Greg Kroah-Hartman
2021-11-01T09:33:50Z

From: Nick Desaulniers <ndesaulniers@google.com>

commit e6a0c958bdf9b2e1b57501fc9433a461f0a6aadd upstream.

A kernel built with CONFIG_THUMB2_KERNEL=y and using clang as the
assembler could generate non-naturally-aligned v7wbi_tlb_fns which
results in a boot failure. The original commit adding the macro missed
the .align directive on this data.

Link: https://github.com/ClangBuiltLinux/linux/issues/1447
Link: https://lore.kernel.org/all/0699da7b-354f-aecc-a62f-e25693209af4@linaro.org/
Debugged-by: Ard Biesheuvel <ardb@kernel.org>
Debugged-by: Nathan Chancellor <nathan@kernel.org>
Debugged-by: Richard Henderson <richard.henderson@linaro.org>

Fixes: 66a625a88174 ("ARM: mm: proc-macros: Add generic proc/cache/tlb struct definition macros")
Suggested-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
arch/arm/mm/proc-macros.S | 1 +
1 file changed, 1 insertion(+)

--- a/arch/arm/mm/proc-macros.S
+++ b/arch/arm/mm/proc-macros.S
@@ -340,6 +340,7 @@ ENTRY(\name\()_cache_fns)

.macro define_tlb_functions name:req, flags_up:req, flags_smp
.type \name\()_tlb_fns, #object
+ .align 2
ENTRY(\name\()_tlb_fns)
.long \name\()_flush_user_tlb_range
.long \name\()_flush_kern_tlb_range