From d1f684e46bbd43eac5c6fb00906c57425d7022a6 Mon Sep 17 00:00:00 2001 From: Mark Rutland Date: Thu, 1 Sep 2022 14:06:43 +0100 Subject: arm64: stacktrace: rework stack boundary discovery In subsequent patches we'll want to acquire the stack boundaries ahead-of-time, and we'll need to be able to acquire the relevant stack_info regardless of whether we have an object the happens to be on the stack. This patch replaces the on_XXX_stack() helpers with stackinfo_get_XXX() helpers, with the caller being responsible for the checking whether an object is on a relevant stack. For the moment this is moved into the on_accessible_stack() functions, making these slightly larger; subsequent patches will remove the on_accessible_stack() functions and simplify the logic. The on_irq_stack() and on_task_stack() helpers are kept as these are used by IRQ entry sequences and stackleak respectively. As they're only used as predicates, the stack_info pointer parameter is removed in both cases. As the on_accessible_stack() functions are always passed a non-NULL info pointer, these now update info unconditionally. When updating the type to STACK_TYPE_UNKNOWN, the low/high bounds are also modified, but as these will not be consumed this should have no adverse affect. There should be no functional change as a result of this patch. Signed-off-by: Mark Rutland Reviewed-by: Kalesh Singh Reviewed-by: Madhavan T. Venkataraman Reviewed-by: Mark Brown Cc: Fuad Tabba Cc: Marc Zyngier Cc: Will Deacon Link: https://lore.kernel.org/r/20220901130646.1316937-7-mark.rutland@arm.com Signed-off-by: Catalin Marinas --- arch/arm64/kernel/ptrace.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/arm64/kernel/ptrace.c') diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c index eb7c08dfb834..00c05da7112c 100644 --- a/arch/arm64/kernel/ptrace.c +++ b/arch/arm64/kernel/ptrace.c @@ -121,7 +121,7 @@ static bool regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr) { return ((addr & ~(THREAD_SIZE - 1)) == (kernel_stack_pointer(regs) & ~(THREAD_SIZE - 1))) || - on_irq_stack(addr, sizeof(unsigned long), NULL); + on_irq_stack(addr, sizeof(unsigned long)); } /** -- cgit v1.2.3 From 0027d9c6c7b57b61b82f7275633ba89d0de2d2fd Mon Sep 17 00:00:00 2001 From: Mark Brown Date: Mon, 29 Aug 2022 16:49:20 +0100 Subject: arm64/ptrace: Support access to TPIDR2_EL0 SME introduces an additional EL0 register, TPIDR2_EL0, intended for use by userspace as part of the SME. Provide ptrace access to it through the existing NT_ARM_TLS regset used for TPIDR_EL0 by expanding it to two registers with TPIDR2_EL0 being the second one. Existing programs that query the size of the register set will be able to observe the increased size of the register set. Programs that assume the register set is single register will see no change. On systems that do not support SME TPIDR2_EL0 will read as 0 and writes will be ignored, support for SME should be queried via hwcaps as normal. Signed-off-by: Mark Brown Link: https://lore.kernel.org/r/20220829154921.837871-4-broonie@kernel.org Signed-off-by: Catalin Marinas --- arch/arm64/kernel/ptrace.c | 25 ++++++++++++++++++++----- 1 file changed, 20 insertions(+), 5 deletions(-) (limited to 'arch/arm64/kernel/ptrace.c') diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c index eb7c08dfb834..0e9764f73d61 100644 --- a/arch/arm64/kernel/ptrace.c +++ b/arch/arm64/kernel/ptrace.c @@ -666,10 +666,18 @@ static int fpr_set(struct task_struct *target, const struct user_regset *regset, static int tls_get(struct task_struct *target, const struct user_regset *regset, struct membuf to) { + int ret; + if (target == current) tls_preserve_current_state(); - return membuf_store(&to, target->thread.uw.tp_value); + ret = membuf_store(&to, target->thread.uw.tp_value); + if (system_supports_tpidr2()) + ret = membuf_store(&to, target->thread.tpidr2_el0); + else + ret = membuf_zero(&to, sizeof(u64)); + + return ret; } static int tls_set(struct task_struct *target, const struct user_regset *regset, @@ -677,13 +685,20 @@ static int tls_set(struct task_struct *target, const struct user_regset *regset, const void *kbuf, const void __user *ubuf) { int ret; - unsigned long tls = target->thread.uw.tp_value; + unsigned long tls[2]; - ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &tls, 0, -1); + tls[0] = target->thread.uw.tp_value; + if (system_supports_sme()) + tls[1] = target->thread.tpidr2_el0; + + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, tls, 0, count); if (ret) return ret; - target->thread.uw.tp_value = tls; + target->thread.uw.tp_value = tls[0]; + if (system_supports_sme()) + target->thread.tpidr2_el0 = tls[1]; + return ret; } @@ -1392,7 +1407,7 @@ static const struct user_regset aarch64_regsets[] = { }, [REGSET_TLS] = { .core_note_type = NT_ARM_TLS, - .n = 1, + .n = 2, .size = sizeof(void *), .align = sizeof(void *), .regset_get = tls_get, -- cgit v1.2.3