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| author | Ard Biesheuvel <ardb@kernel.org> | 2020-09-14 10:48:20 +0200 |
|---|---|---|
| committer | Ard Biesheuvel <ardb@kernel.org> | 2020-10-28 17:05:39 +0100 |
| commit | 450abd38fe6c6313ce9bdd9dce81c1dd604f6fb0 (patch) | |
| tree | 40d8d29bfe5389007a3128447f890ceda61afc37 /arch/arm/kernel/head.S | |
| parent | ARM: head.S: use PC-relative insn sequence for secondary_data (diff) | |
| download | linux-450abd38fe6c6313ce9bdd9dce81c1dd604f6fb0.tar.xz linux-450abd38fe6c6313ce9bdd9dce81c1dd604f6fb0.zip | |
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/kernel/head.S')
| -rw-r--r-- | arch/arm/kernel/head.S | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S index 478506b2d51f..cdc79fcee43e 100644 --- a/arch/arm/kernel/head.S +++ b/arch/arm/kernel/head.S @@ -546,14 +546,15 @@ smp_on_up: __do_fixup_smp_on_up: cmp r4, r5 reths lr - ldmia r4!, {r0, r6} - ARM( str r6, [r0, r3] ) - THUMB( add r0, r0, r3 ) + ldmia r4, {r0, r6} + ARM( str r6, [r0, r4] ) + THUMB( add r0, r0, r4 ) + add r4, r4, #8 #ifdef __ARMEB__ THUMB( mov r6, r6, ror #16 ) @ Convert word order for big-endian. #endif THUMB( strh r6, [r0], #2 ) @ For Thumb-2, store as two halfwords - THUMB( mov r6, r6, lsr #16 ) @ to be robust against misaligned r3. + THUMB( mov r6, r6, lsr #16 ) @ to be robust against misaligned r0. THUMB( strh r6, [r0] ) b __do_fixup_smp_on_up ENDPROC(__do_fixup_smp_on_up) @@ -562,7 +563,6 @@ ENTRY(fixup_smp) stmfd sp!, {r4 - r6, lr} mov r4, r0 add r5, r0, r1 - mov r3, #0 bl __do_fixup_smp_on_up ldmfd sp!, {r4 - r6, pc} ENDPROC(fixup_smp) |