diff options
| author | Russell King <rmk+kernel@armlinux.org.uk> | 2018-05-14 15:20:21 +0200 |
|---|---|---|
| committer | Russell King <rmk+kernel@armlinux.org.uk> | 2018-05-31 11:40:32 +0200 |
| commit | f5fe12b1eaee220ce62ff9afb8b90929c396595f (patch) | |
| tree | c1a1264964eb0d9e6e4ed77ee2788139553108d6 /arch/arm/mm/proc-v7.S | |
| parent | ARM: spectre-v2: add Cortex A8 and A15 validation of the IBE bit (diff) | |
| download | linux-f5fe12b1eaee220ce62ff9afb8b90929c396595f.tar.xz linux-f5fe12b1eaee220ce62ff9afb8b90929c396595f.zip | |
ARM: spectre-v2: harden user aborts in kernel space
In order to prevent aliasing attacks on the branch predictor,
invalidate the BTB or instruction cache on CPUs that are known to be
affected when taking an abort on a address that is outside of a user
task limit:
Cortex A8, A9, A12, A17, A73, A75: flush BTB.
Cortex A15, Brahma B15: invalidate icache.
If the IBE bit is not set, then there is little point to enabling the
workaround.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Boot-tested-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Diffstat (limited to 'arch/arm/mm/proc-v7.S')
| -rw-r--r-- | arch/arm/mm/proc-v7.S | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/arch/arm/mm/proc-v7.S b/arch/arm/mm/proc-v7.S index fa9214036fb3..79510011e7eb 100644 --- a/arch/arm/mm/proc-v7.S +++ b/arch/arm/mm/proc-v7.S @@ -532,8 +532,10 @@ __v7_setup_stack: __INITDATA + .weak cpu_v7_bugs_init + @ define struct processor (see <asm/proc-fns.h> and proc-macros.S) - define_processor_functions v7, dabort=v7_early_abort, pabort=v7_pabort, suspend=1 + define_processor_functions v7, dabort=v7_early_abort, pabort=v7_pabort, suspend=1, bugs=cpu_v7_bugs_init #ifdef CONFIG_HARDEN_BRANCH_PREDICTOR @ generic v7 bpiall on context switch @@ -548,7 +550,7 @@ __v7_setup_stack: globl_equ cpu_v7_bpiall_do_suspend, cpu_v7_do_suspend globl_equ cpu_v7_bpiall_do_resume, cpu_v7_do_resume #endif - define_processor_functions v7_bpiall, dabort=v7_early_abort, pabort=v7_pabort, suspend=1 + define_processor_functions v7_bpiall, dabort=v7_early_abort, pabort=v7_pabort, suspend=1, bugs=cpu_v7_bugs_init #define HARDENED_BPIALL_PROCESSOR_FUNCTIONS v7_bpiall_processor_functions #else @@ -584,7 +586,7 @@ __v7_setup_stack: globl_equ cpu_ca9mp_switch_mm, cpu_v7_switch_mm #endif globl_equ cpu_ca9mp_set_pte_ext, cpu_v7_set_pte_ext - define_processor_functions ca9mp, dabort=v7_early_abort, pabort=v7_pabort, suspend=1 + define_processor_functions ca9mp, dabort=v7_early_abort, pabort=v7_pabort, suspend=1, bugs=cpu_v7_bugs_init #endif @ Cortex-A15 - needs iciallu switch_mm for hardening |