From: Ard Biesheuvel ardb@kernel.org
mainline inclusion from mainline-5.11-rc1 commit 0e3db6c9d7f6fd0ee263325027e8d3fdac5a4c9e category: bugfix bugzilla: 46882 CVE: NA
------------------------------------------------- Declutter the code in __fixup_pv_table() by using the new adr_l/str_l macros to take PC relative references to external symbols, and by using the value of PHYS_OFFSET passed in r8 to calculate the p2v offset.
Acked-by: Nicolas Pitre nico@fluxnic.net Reviewed-by: Linus Walleij linus.walleij@linaro.org Signed-off-by: Ard Biesheuvel ardb@kernel.org (cherry picked from commit 0e3db6c9d7f6fd0ee263325027e8d3fdac5a4c9e) Signed-off-by: Zhao Hongjiang zhaohongjiang@huawei.com --- arch/arm/kernel/phys2virt.S | 34 ++++++++++++++-------------------- 1 file changed, 14 insertions(+), 20 deletions(-)
diff --git a/arch/arm/kernel/phys2virt.S b/arch/arm/kernel/phys2virt.S index 8e4be15e1559..be8fb0d89877 100644 --- a/arch/arm/kernel/phys2virt.S +++ b/arch/arm/kernel/phys2virt.S @@ -29,33 +29,27 @@ */ __HEAD ENTRY(__fixup_pv_table) - adr r0, 1f - ldmia r0, {r3-r7} - mvn ip, #0 - subs r3, r0, r3 @ PHYS_OFFSET - PAGE_OFFSET - add r4, r4, r3 @ adjust table start address - add r5, r5, r3 @ adjust table end address - add r6, r6, r3 @ adjust __pv_phys_pfn_offset address - add r7, r7, r3 @ adjust __pv_offset address mov r0, r8, lsr #PAGE_SHIFT @ convert to PFN - str r0, [r6] @ save computed PHYS_OFFSET to __pv_phys_pfn_offset - strcc ip, [r7, #HIGH_OFFSET] @ save to __pv_offset high bits - mov r6, r3, lsr #24 @ constant for add/sub instructions - teq r3, r6, lsl #24 @ must be 16MiB aligned + str_l r0, __pv_phys_pfn_offset, r3 + + adr_l r0, __pv_offset + subs r3, r8, #PAGE_OFFSET @ PHYS_OFFSET - PAGE_OFFSET + mvn ip, #0 + strcc ip, [r0, #HIGH_OFFSET] @ save to __pv_offset high bits + str r3, [r0, #LOW_OFFSET] @ save to __pv_offset low bits + + mov r0, r3, lsr #24 @ constant for add/sub instructions + teq r3, r0, lsl #24 @ must be 16MiB aligned bne 0f - str r3, [r7, #LOW_OFFSET] @ save to __pv_offset low bits + + adr_l r4, __pv_table_begin + adr_l r5, __pv_table_end b __fixup_a_pv_table + 0: mov r0, r0 @ deadloop on error b 0b ENDPROC(__fixup_pv_table)
- .align -1: .long . - .long __pv_table_begin - .long __pv_table_end -2: .long __pv_phys_pfn_offset - .long __pv_offset - .text __fixup_a_pv_table: adr_l r6, __pv_offset