From d56e7aa4116720bc4de761110f1bc9da6e5394c9 Mon Sep 17 00:00:00 2001 From: Suzuki K Poulose Date: Thu, 24 Oct 2019 14:47:56 +0200 Subject: arm64: capabilities: Move errata work around check on boot CPU [ Upstream commit 5e91107b06811f0ca147cebbedce53626c9c4443 ] We trigger CPU errata work around check on the boot CPU from smp_prepare_boot_cpu() to make sure that we run the checks only after the CPU feature infrastructure is initialised. While this is correct, we can also do this from init_cpu_features() which initilises the infrastructure, and is called only on the Boot CPU. This helps to consolidate the CPU capability handling to cpufeature.c. No functional changes. Cc: Will Deacon Cc: Catalin Marinas Cc: Mark Rutland Reviewed-by: Dave Martin Signed-off-by: Suzuki K Poulose Signed-off-by: Will Deacon Signed-off-by: Ard Biesheuvel Signed-off-by: Greg Kroah-Hartman --- arch/arm64/kernel/smp.c | 6 ------ 1 file changed, 6 deletions(-) (limited to 'arch/arm64/kernel/smp.c') diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index b7ad41d7b6ee..e9b8395e24a7 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -449,12 +449,6 @@ void __init smp_prepare_boot_cpu(void) jump_label_init(); cpuinfo_store_boot_cpu(); save_boot_cpu_run_el(); - /* - * Run the errata work around checks on the boot CPU, once we have - * initialised the cpu feature infrastructure from - * cpuinfo_store_boot_cpu() above. - */ - update_cpu_errata_workarounds(); } static u64 __init of_get_cpu_mpidr(struct device_node *dn) -- cgit v1.2.3 From ee0ccd259b4c4e362a75e382dae26b69560429a1 Mon Sep 17 00:00:00 2001 From: Suzuki K Poulose Date: Thu, 24 Oct 2019 14:48:09 +0200 Subject: arm64: capabilities: Change scope of VHE to Boot CPU feature [ Upstream commit 830dcc9f9a7cd26a812522a26efaacf7df6fc365 ] We expect all CPUs to be running at the same EL inside the kernel with or without VHE enabled and we have strict checks to ensure that any mismatch triggers a kernel panic. If VHE is enabled, we use the feature based on the boot CPU and all other CPUs should follow. This makes it a perfect candidate for a capability based on the boot CPU, which should be matched by all the CPUs (both when is ON and OFF). This saves us some not-so-pretty hooks and special code, just for verifying the conflict. The patch also makes the VHE capability entry depend on CONFIG_ARM64_VHE. Cc: Marc Zyngier Cc: Will Deacon Reviewed-by: Dave Martin Signed-off-by: Suzuki K Poulose Signed-off-by: Will Deacon Signed-off-by: Ard Biesheuvel Signed-off-by: Greg Kroah-Hartman --- arch/arm64/kernel/smp.c | 38 -------------------------------------- 1 file changed, 38 deletions(-) (limited to 'arch/arm64/kernel/smp.c') diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index e9b8395e24a7..a683cd499515 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -83,43 +83,6 @@ enum ipi_msg_type { IPI_WAKEUP }; -#ifdef CONFIG_ARM64_VHE - -/* Whether the boot CPU is running in HYP mode or not*/ -static bool boot_cpu_hyp_mode; - -static inline void save_boot_cpu_run_el(void) -{ - boot_cpu_hyp_mode = is_kernel_in_hyp_mode(); -} - -static inline bool is_boot_cpu_in_hyp_mode(void) -{ - return boot_cpu_hyp_mode; -} - -/* - * Verify that a secondary CPU is running the kernel at the same - * EL as that of the boot CPU. - */ -void verify_cpu_run_el(void) -{ - bool in_el2 = is_kernel_in_hyp_mode(); - bool boot_cpu_el2 = is_boot_cpu_in_hyp_mode(); - - if (in_el2 ^ boot_cpu_el2) { - pr_crit("CPU%d: mismatched Exception Level(EL%d) with boot CPU(EL%d)\n", - smp_processor_id(), - in_el2 ? 2 : 1, - boot_cpu_el2 ? 2 : 1); - cpu_panic_kernel(); - } -} - -#else -static inline void save_boot_cpu_run_el(void) {} -#endif - #ifdef CONFIG_HOTPLUG_CPU static int op_cpu_kill(unsigned int cpu); #else @@ -448,7 +411,6 @@ void __init smp_prepare_boot_cpu(void) */ jump_label_init(); cpuinfo_store_boot_cpu(); - save_boot_cpu_run_el(); } static u64 __init of_get_cpu_mpidr(struct device_node *dn) -- cgit v1.2.3 From 63f1e5fb8f1ed58562fff5258bf8bdb686fc0544 Mon Sep 17 00:00:00 2001 From: Steve Capper Date: Thu, 6 Dec 2018 22:50:40 +0000 Subject: arm64: mm: Prevent mismatched 52-bit VA support [ Upstream commit a96a33b1ca57dbea4285893dedf290aeb8eb090b ] For cases where there is a mismatch in ARMv8.2-LVA support between CPUs we have to be careful in allowing secondary CPUs to boot if 52-bit virtual addresses have already been enabled on the boot CPU. This patch adds code to the secondary startup path. If the boot CPU has enabled 52-bit VAs then ID_AA64MMFR2_EL1 is checked to see if the secondary can also enable 52-bit support. If not, the secondary is prevented from booting and an error message is displayed indicating why. Technically this patch could be implemented using the cpufeature code when considering 52-bit userspace support. However, we employ low level checks here as the cpufeature code won't be able to run if we have mismatched 52-bit kernel va support. Signed-off-by: Steve Capper Signed-off-by: Will Deacon Signed-off-by: Sasha Levin --- arch/arm64/kernel/smp.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'arch/arm64/kernel/smp.c') diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index a683cd499515..0881dfab10f8 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -106,6 +106,7 @@ static int boot_secondary(unsigned int cpu, struct task_struct *idle) } static DECLARE_COMPLETION(cpu_running); +bool va52mismatch __ro_after_init; int __cpu_up(unsigned int cpu, struct task_struct *idle) { @@ -135,6 +136,10 @@ int __cpu_up(unsigned int cpu, struct task_struct *idle) if (!cpu_online(cpu)) { pr_crit("CPU%u: failed to come online\n", cpu); + + if (IS_ENABLED(CONFIG_ARM64_52BIT_VA) && va52mismatch) + pr_crit("CPU%u: does not support 52-bit VAs\n", cpu); + ret = -EIO; } } else { -- cgit v1.2.3 From 7324581318f696cbb615d796657b11eae041c353 Mon Sep 17 00:00:00 2001 From: Suzuki K Poulose Date: Mon, 10 Dec 2018 18:07:33 +0000 Subject: arm64: smp: Handle errors reported by the firmware [ Upstream commit f357b3a7e17af7736d67d8267edc1ed3d1dd9391 ] The __cpu_up() routine ignores the errors reported by the firmware for a CPU bringup operation and looks for the error status set by the booting CPU. If the CPU never entered the kernel, we could end up in assuming stale error status, which otherwise would have been set/cleared appropriately by the booting CPU. Reported-by: Steve Capper Cc: Will Deacon Signed-off-by: Suzuki K Poulose Signed-off-by: Will Deacon Signed-off-by: Sasha Levin --- arch/arm64/kernel/smp.c | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/arm64/kernel/smp.c') diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index 0881dfab10f8..909bf3926fd2 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -144,6 +144,7 @@ int __cpu_up(unsigned int cpu, struct task_struct *idle) } } else { pr_err("CPU%u: failed to boot: %d\n", cpu, ret); + return ret; } secondary_data.task = NULL; -- cgit v1.2.3