From 0dc14aa94ccd8ba35eb17a0f9b123d1566efd39e Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Wed, 20 Apr 2022 09:44:51 +0100 Subject: ARM: 9196/1: spectre-bhb: enable for Cortex-A15 The Spectre-BHB mitigations were inadvertently left disabled for Cortex-A15, due to the fact that cpu_v7_bugs_init() is not called in that case. So fix that. Fixes: b9baf5c8c5c3 ("ARM: Spectre-BHB workaround") Signed-off-by: Ard Biesheuvel Signed-off-by: Russell King (Oracle) --- arch/arm/mm/proc-v7-bugs.c | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/arm/mm/proc-v7-bugs.c b/arch/arm/mm/proc-v7-bugs.c index 06dbfb968182..fb9f3eb6bf48 100644 --- a/arch/arm/mm/proc-v7-bugs.c +++ b/arch/arm/mm/proc-v7-bugs.c @@ -288,6 +288,7 @@ void cpu_v7_ca15_ibe(void) { if (check_spectre_auxcr(this_cpu_ptr(&spectre_warned), BIT(0))) cpu_v7_spectre_v2_init(); + cpu_v7_spectre_bhb_init(); } void cpu_v7_bugs_init(void) -- cgit From 3cfb3019979666bdf33a1010147363cf05e0f17b Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Wed, 20 Apr 2022 09:46:17 +0100 Subject: ARM: 9197/1: spectre-bhb: fix loop8 sequence for Thumb2 In Thumb2, 'b . + 4' produces a branch instruction that uses a narrow encoding, and so it does not jump to the following instruction as expected. So use W(b) instead. Fixes: 6c7cb60bff7a ("ARM: fix Thumb2 regression with Spectre BHB") Signed-off-by: Ard Biesheuvel Signed-off-by: Russell King (Oracle) --- arch/arm/kernel/entry-armv.S | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S index 06508698abb8..7a8682468a84 100644 --- a/arch/arm/kernel/entry-armv.S +++ b/arch/arm/kernel/entry-armv.S @@ -1145,7 +1145,7 @@ vector_bhb_loop8_\name: @ bhb workaround mov r0, #8 -3: b . + 4 +3: W(b) . + 4 subs r0, r0, #1 bne 3b dsb -- cgit