[PATCH 4.9 01/20] ARM: 9133/1: mm: proc-macros: ensure *_tlb_fns are 4B aligned

From: Greg Kroah-Hartman
Date: Mon Nov 01 2021 - 05:20:28 EST


From: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>

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@xxxxxxxxxx/
Debugged-by: Ard Biesheuvel <ardb@xxxxxxxxxx>
Debugged-by: Nathan Chancellor <nathan@xxxxxxxxxx>
Debugged-by: Richard Henderson <richard.henderson@xxxxxxxxxx>

Fixes: 66a625a88174 ("ARM: mm: proc-macros: Add generic proc/cache/tlb struct definition macros")
Suggested-by: Ard Biesheuvel <ardb@xxxxxxxxxx>
Acked-by: Ard Biesheuvel <ardb@xxxxxxxxxx>
Signed-off-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
Tested-by: Nathan Chancellor <nathan@xxxxxxxxxx>
Signed-off-by: Russell King (Oracle) <rmk+kernel@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
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
@@ -343,6 +343,7 @@ 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