From 965861d66fad6ce07bd5c5ecbe6514bc50b8fc11 Mon Sep 17 00:00:00 2001 From: Mark Rutland Date: Thu, 2 Feb 2017 17:32:15 +0000 Subject: arm64: ensure __raw_read_system_reg() is self-consistent We recently discovered that __raw_read_system_reg() erroneously mapped sysreg IDs to the wrong registers. To ensure that we don't get hit by a similar issue in future, this patch makes __raw_read_system_reg() use a macro for each case statement, ensuring that each case reads the correct register. To ensure that this patch hasn't introduced an issue, I've binary-diffed the object files before and after this patch. No code or data sections differ (though some debug section differ due to line numbering changing). Signed-off-by: Mark Rutland Cc: Catalin Marinas Cc: Suzuki K Poulose Cc: Will Deacon Signed-off-by: Will Deacon --- arch/arm64/kernel/cpufeature.c | 64 ++++++++++++++++++++++-------------------- 1 file changed, 34 insertions(+), 30 deletions(-) (limited to 'arch') diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index 0688b9a3adeb..1ee5357d0c6a 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -645,6 +645,9 @@ u64 read_system_reg(u32 id) return regp->sys_val; } +#define read_sysreg_case(r) \ + case r: return read_sysreg_s(r) + /* * __raw_read_system_reg() - Used by a STARTING cpu before cpuinfo is populated. * Read the system register on the current CPU @@ -652,36 +655,37 @@ u64 read_system_reg(u32 id) static u64 __raw_read_system_reg(u32 sys_id) { switch (sys_id) { - case SYS_ID_PFR0_EL1: return read_cpuid(ID_PFR0_EL1); - case SYS_ID_PFR1_EL1: return read_cpuid(ID_PFR1_EL1); - case SYS_ID_DFR0_EL1: return read_cpuid(ID_DFR0_EL1); - case SYS_ID_MMFR0_EL1: return read_cpuid(ID_MMFR0_EL1); - case SYS_ID_MMFR1_EL1: return read_cpuid(ID_MMFR1_EL1); - case SYS_ID_MMFR2_EL1: return read_cpuid(ID_MMFR2_EL1); - case SYS_ID_MMFR3_EL1: return read_cpuid(ID_MMFR3_EL1); - case SYS_ID_ISAR0_EL1: return read_cpuid(ID_ISAR0_EL1); - case SYS_ID_ISAR1_EL1: return read_cpuid(ID_ISAR1_EL1); - case SYS_ID_ISAR2_EL1: return read_cpuid(ID_ISAR2_EL1); - case SYS_ID_ISAR3_EL1: return read_cpuid(ID_ISAR3_EL1); - case SYS_ID_ISAR4_EL1: return read_cpuid(ID_ISAR4_EL1); - case SYS_ID_ISAR5_EL1: return read_cpuid(ID_ISAR5_EL1); - case SYS_MVFR0_EL1: return read_cpuid(MVFR0_EL1); - case SYS_MVFR1_EL1: return read_cpuid(MVFR1_EL1); - case SYS_MVFR2_EL1: return read_cpuid(MVFR2_EL1); - - case SYS_ID_AA64PFR0_EL1: return read_cpuid(ID_AA64PFR0_EL1); - case SYS_ID_AA64PFR1_EL1: return read_cpuid(ID_AA64PFR1_EL1); - case SYS_ID_AA64DFR0_EL1: return read_cpuid(ID_AA64DFR0_EL1); - case SYS_ID_AA64DFR1_EL1: return read_cpuid(ID_AA64DFR1_EL1); - case SYS_ID_AA64MMFR0_EL1: return read_cpuid(ID_AA64MMFR0_EL1); - case SYS_ID_AA64MMFR1_EL1: return read_cpuid(ID_AA64MMFR1_EL1); - case SYS_ID_AA64MMFR2_EL1: return read_cpuid(ID_AA64MMFR2_EL1); - case SYS_ID_AA64ISAR0_EL1: return read_cpuid(ID_AA64ISAR0_EL1); - case SYS_ID_AA64ISAR1_EL1: return read_cpuid(ID_AA64ISAR1_EL1); - - case SYS_CNTFRQ_EL0: return read_cpuid(CNTFRQ_EL0); - case SYS_CTR_EL0: return read_cpuid(CTR_EL0); - case SYS_DCZID_EL0: return read_cpuid(DCZID_EL0); + read_sysreg_case(SYS_ID_PFR0_EL1); + read_sysreg_case(SYS_ID_PFR1_EL1); + read_sysreg_case(SYS_ID_DFR0_EL1); + read_sysreg_case(SYS_ID_MMFR0_EL1); + read_sysreg_case(SYS_ID_MMFR1_EL1); + read_sysreg_case(SYS_ID_MMFR2_EL1); + read_sysreg_case(SYS_ID_MMFR3_EL1); + read_sysreg_case(SYS_ID_ISAR0_EL1); + read_sysreg_case(SYS_ID_ISAR1_EL1); + read_sysreg_case(SYS_ID_ISAR2_EL1); + read_sysreg_case(SYS_ID_ISAR3_EL1); + read_sysreg_case(SYS_ID_ISAR4_EL1); + read_sysreg_case(SYS_ID_ISAR5_EL1); + read_sysreg_case(SYS_MVFR0_EL1); + read_sysreg_case(SYS_MVFR1_EL1); + read_sysreg_case(SYS_MVFR2_EL1); + + read_sysreg_case(SYS_ID_AA64PFR0_EL1); + read_sysreg_case(SYS_ID_AA64PFR1_EL1); + read_sysreg_case(SYS_ID_AA64DFR0_EL1); + read_sysreg_case(SYS_ID_AA64DFR1_EL1); + read_sysreg_case(SYS_ID_AA64MMFR0_EL1); + read_sysreg_case(SYS_ID_AA64MMFR1_EL1); + read_sysreg_case(SYS_ID_AA64MMFR2_EL1); + read_sysreg_case(SYS_ID_AA64ISAR0_EL1); + read_sysreg_case(SYS_ID_AA64ISAR1_EL1); + + read_sysreg_case(SYS_CNTFRQ_EL0); + read_sysreg_case(SYS_CTR_EL0); + read_sysreg_case(SYS_DCZID_EL0); + default: BUG(); return 0; -- cgit v1.2.3-59-g8ed1b