diff options
| author | Ard Biesheuvel <ardb@kernel.org> | 2020-09-14 11:48:20 +0300 |
|---|---|---|
| committer | Ard Biesheuvel <ardb@kernel.org> | 2020-10-28 17:05:39 +0100 |
| commit | 450abd38fe6c6313ce9bdd9dce81c1dd604f6fb0 (patch) | |
| tree | 40d8d29bfe5389007a3128447f890ceda61afc37 /arch/arm/include | |
| parent | 91580f0dbf24c6d616091526a900213bc7aa48fe (diff) | |
ARM: kernel: use relative references for UP/SMP alternatives
Currently, the .alt.smp.init section contains the virtual addresses
of the patch sites. Since patching may occur both before and after
switching into virtual mode, this requires some manual handling of
the address when applying the UP alternative.
Let's simplify this by using relative offsets in the table entries:
this allows us to simply add each entry's address to its contents,
regardless of whether we are running in virtual mode or not.
Reviewed-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Diffstat (limited to 'arch/arm/include')
| -rw-r--r-- | arch/arm/include/asm/assembler.h | 4 | ||||
| -rw-r--r-- | arch/arm/include/asm/processor.h | 2 |
2 files changed, 3 insertions, 3 deletions
diff --git a/arch/arm/include/asm/assembler.h b/arch/arm/include/asm/assembler.h index 72627c5fb3b2..6ed30421f697 100644 --- a/arch/arm/include/asm/assembler.h +++ b/arch/arm/include/asm/assembler.h @@ -259,7 +259,7 @@ */ #define ALT_UP(instr...) \ .pushsection ".alt.smp.init", "a" ;\ - .long 9998b ;\ + .long 9998b - . ;\ 9997: instr ;\ .if . - 9997b == 2 ;\ nop ;\ @@ -270,7 +270,7 @@ .popsection #define ALT_UP_B(label) \ .pushsection ".alt.smp.init", "a" ;\ - .long 9998b ;\ + .long 9998b - . ;\ W(b) . + (label - 9998b) ;\ .popsection #else diff --git a/arch/arm/include/asm/processor.h b/arch/arm/include/asm/processor.h index b9241051e5cb..9e6b97286307 100644 --- a/arch/arm/include/asm/processor.h +++ b/arch/arm/include/asm/processor.h @@ -96,7 +96,7 @@ unsigned long get_wchan(struct task_struct *p); #define __ALT_SMP_ASM(smp, up) \ "9998: " smp "\n" \ " .pushsection \".alt.smp.init\", \"a\"\n" \ - " .long 9998b\n" \ + " .long 9998b - .\n" \ " " up "\n" \ " .popsection\n" #else |