Add RSEQ, restartable sequence, support and related selftest to RISCV. The Kconfig option HAVE_REGS_AND_STACK_ACCESS_API is also required by RSEQ because RSEQ will modify the content of pt_regs.sepc through instruction_pointer_set() during the fixup procedure. In order to select the config HAVE_REGS_AND_STACK_ACCESS_API, the missing APIs for accessing pt_regs are also added in this patch set.
The relevant RSEQ tests in kselftest require the Binutils patch "RISC-V: Fix linker problems with TLS copy relocs" to avoid placing PREINIT_ARRAY and TLS variable of librseq.so at the same address. https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git%3Ba=commit%3Bh=3e7b... A segmental fault will happen if the Binutils misses this patch.
Vincent Chen (3): riscv: add required functions to enable HAVE_REGS_AND_STACK_ACCESS_API riscv: Add support for restartable sequence rseq/selftests: Add support for riscv
arch/riscv/Kconfig | 2 + arch/riscv/include/asm/ptrace.h | 29 +- arch/riscv/kernel/entry.S | 4 + arch/riscv/kernel/ptrace.c | 99 +++++ arch/riscv/kernel/signal.c | 3 + tools/testing/selftests/rseq/param_test.c | 23 ++ tools/testing/selftests/rseq/rseq-riscv.h | 622 ++++++++++++++++++++++++++++++ tools/testing/selftests/rseq/rseq.h | 2 + 8 files changed, 783 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/rseq/rseq-riscv.h
In order to select HAVE_REGS_AND_STACK_ACCESS_API, adding the APIs required by kprobes to access pt_regs and stack entries to the RISC-V ports.
Signed-off-by: Patrick Stählin me@packi.ch Signed-off-by: Vincent Chen vincent.chen@sifive.com --- arch/riscv/Kconfig | 1 + arch/riscv/include/asm/ptrace.h | 29 +++++++++++- arch/riscv/kernel/ptrace.c | 99 +++++++++++++++++++++++++++++++++++++++++ 3 files changed, 128 insertions(+), 1 deletion(-)
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 8eebbc8860bb..d5bbf4223fd2 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -61,6 +61,7 @@ config RISCV select SPARSEMEM_STATIC if 32BIT select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU select HAVE_ARCH_MMAP_RND_BITS + select HAVE_REGS_AND_STACK_ACCESS_API
config ARCH_MMAP_RND_BITS_MIN default 18 if 64BIT diff --git a/arch/riscv/include/asm/ptrace.h b/arch/riscv/include/asm/ptrace.h index d48d1e13973c..635b7b5506ec 100644 --- a/arch/riscv/include/asm/ptrace.h +++ b/arch/riscv/include/asm/ptrace.h @@ -8,6 +8,7 @@
#include <uapi/asm/ptrace.h> #include <asm/csr.h> +#include <linux/compiler.h>
#ifndef __ASSEMBLY__
@@ -59,7 +60,7 @@ struct pt_regs { #endif
#define user_mode(regs) (((regs)->sstatus & SR_SPP) == 0) - +#define MAX_REG_OFFSET offsetof(struct pt_regs, orig_a0)
/* Helpers for working with the instruction pointer */ static inline unsigned long instruction_pointer(struct pt_regs *regs) @@ -79,6 +80,12 @@ static inline unsigned long user_stack_pointer(struct pt_regs *regs) { return regs->sp; } + +static inline unsigned long kernel_stack_pointer(struct pt_regs *regs) +{ + return regs->sp; +} + static inline void user_stack_pointer_set(struct pt_regs *regs, unsigned long val) { @@ -101,6 +108,26 @@ static inline unsigned long regs_return_value(struct pt_regs *regs) return regs->a0; }
+int regs_query_register_offset(const char *name); + +unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n); +/** + * regs_get_register() - get register value from its offset + * @regs: pt_regs from which register value is gotten + * @offset: offset of the register. + * + * regs_get_register returns the value of a register whose offset from @regs. + * The @offset is the offset of the register in struct pt_regs. + * If @offset is bigger than MAX_REG_OFFSET, this returns 0. + */ +static inline unsigned long regs_get_register(struct pt_regs *regs, + unsigned int offset) +{ + if (unlikely(offset > MAX_REG_OFFSET)) + return 0; + + return *(unsigned long *)((unsigned long)regs + offset); +} #endif /* __ASSEMBLY__ */
#endif /* _ASM_RISCV_PTRACE_H */ diff --git a/arch/riscv/kernel/ptrace.c b/arch/riscv/kernel/ptrace.c index 1252113ef8b2..2ae450d67659 100644 --- a/arch/riscv/kernel/ptrace.c +++ b/arch/riscv/kernel/ptrace.c @@ -125,6 +125,105 @@ const struct user_regset_view *task_user_regset_view(struct task_struct *task) return &riscv_user_native_view; }
+struct pt_regs_offset { + const char *name; + int offset; +}; + +#define REG_OFFSET_NAME(r) {.name = #r, .offset = offsetof(struct pt_regs, r)} +#define REG_OFFSET_END {.name = NULL, .offset = 0} + +static const struct pt_regs_offset regoffset_table[] = { + REG_OFFSET_NAME(sepc), + REG_OFFSET_NAME(ra), + REG_OFFSET_NAME(sp), + REG_OFFSET_NAME(gp), + REG_OFFSET_NAME(tp), + REG_OFFSET_NAME(t0), + REG_OFFSET_NAME(t1), + REG_OFFSET_NAME(t2), + REG_OFFSET_NAME(s0), + REG_OFFSET_NAME(s1), + REG_OFFSET_NAME(a0), + REG_OFFSET_NAME(a1), + REG_OFFSET_NAME(a2), + REG_OFFSET_NAME(a3), + REG_OFFSET_NAME(a4), + REG_OFFSET_NAME(a5), + REG_OFFSET_NAME(a6), + REG_OFFSET_NAME(a7), + REG_OFFSET_NAME(s2), + REG_OFFSET_NAME(s3), + REG_OFFSET_NAME(s4), + REG_OFFSET_NAME(s5), + REG_OFFSET_NAME(s6), + REG_OFFSET_NAME(s7), + REG_OFFSET_NAME(s8), + REG_OFFSET_NAME(s9), + REG_OFFSET_NAME(s10), + REG_OFFSET_NAME(s11), + REG_OFFSET_NAME(t3), + REG_OFFSET_NAME(t4), + REG_OFFSET_NAME(t5), + REG_OFFSET_NAME(t6), + REG_OFFSET_NAME(sstatus), + REG_OFFSET_NAME(sbadaddr), + REG_OFFSET_NAME(scause), + REG_OFFSET_NAME(orig_a0), + REG_OFFSET_END, +}; + +/** + * regs_query_register_offset() - query register offset from its name + * @name: the name of a register + * + * regs_query_register_offset() returns the offset of a register in struct + * pt_regs from its name. If the name is invalid, this returns -EINVAL; + */ +int regs_query_register_offset(const char *name) +{ + const struct pt_regs_offset *roff; + + for (roff = regoffset_table; roff->name != NULL; roff++) + if (!strcmp(roff->name, name)) + return roff->offset; + return -EINVAL; +} + +/** + * regs_within_kernel_stack() - check the address in the stack + * @regs: pt_regs which contains kernel stack pointer. + * @addr: address which is checked. + * + * regs_within_kernel_stack() checks @addr is within the kernel stack page(s). + * If @addr is within the kernel stack, it returns true. If not, returns false. + */ +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)); +} + +/** + * regs_get_kernel_stack_nth() - get Nth entry of the stack + * @regs: pt_regs which contains kernel stack pointer. + * @n: stack entry number. + * + * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which + * is specified by @regs. If the @n th entry is NOT in the kernel stack, + * this returns 0. + */ +unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n) +{ + unsigned long *addr = (unsigned long *)kernel_stack_pointer(regs); + + addr += n; + if (regs_within_kernel_stack(regs, (unsigned long)addr)) + return *addr; + else + return 0; +} + void ptrace_disable(struct task_struct *child) { clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
Hi Vincent,
On Tue, 5 Nov 2019, Vincent Chen wrote:
In order to select HAVE_REGS_AND_STACK_ACCESS_API, adding the APIs required by kprobes to access pt_regs and stack entries to the RISC-V ports.
Signed-off-by: Patrick Stählin me@packi.ch Signed-off-by: Vincent Chen vincent.chen@sifive.com
As I understand it, this patch hasn't been signed off on by Patrick. I've sent him an E-mail asking him whether he's willing to add his Signed-off-by:, but haven't heard back from it.
From our discussions, I understand that this patch is based partially on some of his earlier, public, kprobes work. In lieu of any response from Patrick, could you please resend this patch and just note in the commit description that it's partially based on one of his patches, add a Link: line that points to the URL of the patch that it's partially based on, and replace the Signed-off-by: with a Co-developed-by: or something similar?
thanks,
- Paul
On Thu, 21 Nov 2019, Paul Walmsley wrote:
As I understand it, this patch hasn't been signed off on by Patrick. I've sent him an E-mail asking him whether he's willing to add his Signed-off-by:, but haven't heard back from it.
From our discussions, I understand that this patch is based partially on some of his earlier, public, kprobes work. In lieu of any response from Patrick, could you please resend this patch and just note in the commit description that it's partially based on one of his patches, add a Link: line that points to the URL of the patch that it's partially based on, and replace the Signed-off-by: with a Co-developed-by: or something similar?
OK - just looked at the patches more closely, and I think I see what's going on here. This patch looks like a rebased version of this patch:
https://lore.kernel.org/linux-riscv/20181113195804.22825-2-me@packi.ch/
So let's just plan to use an updated version of Patrick's original (below). Please let me know if you have any comments on it or if I missed something -
- Paul
From: Patrick Stählin me@packi.ch Date: Tue, 13 Nov 2018 20:58:03 +0100 Subject: [PATCH] RISC-V: Implement ptrace regs and stack API MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit
Needed for kprobes support. Copied and adapted from arm64 code.
Signed-off-by: Patrick Stählin me@packi.ch [paul.walmsley@sifive.com: updated to apply; fixed checkpatch issues; fixed regs_get_register() kerneldoc] Cc: Vincent Chen vincent.chen@sifive.com Link: https://lore.kernel.org/linux-riscv/20181113195803.CjtBCsUcG9czwiqmPBGKUjvl5... Link: https://lore.kernel.org/linux-riscv/1572919114-3886-1-git-send-email-vincent... Signed-off-by: Paul Walmsley paul.walmsley@sifive.com --- arch/riscv/Kconfig | 1 + arch/riscv/include/asm/ptrace.h | 30 ++++++++++ arch/riscv/kernel/ptrace.c | 99 +++++++++++++++++++++++++++++++++ 3 files changed, 130 insertions(+)
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 8eebbc8860bb..d5bbf4223fd2 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -61,6 +61,7 @@ config RISCV select SPARSEMEM_STATIC if 32BIT select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU select HAVE_ARCH_MMAP_RND_BITS + select HAVE_REGS_AND_STACK_ACCESS_API
config ARCH_MMAP_RND_BITS_MIN default 18 if 64BIT diff --git a/arch/riscv/include/asm/ptrace.h b/arch/riscv/include/asm/ptrace.h index d48d1e13973c..50d37b123a61 100644 --- a/arch/riscv/include/asm/ptrace.h +++ b/arch/riscv/include/asm/ptrace.h @@ -8,6 +8,7 @@
#include <uapi/asm/ptrace.h> #include <asm/csr.h> +#include <linux/compiler.h>
#ifndef __ASSEMBLY__
@@ -60,6 +61,7 @@ struct pt_regs {
#define user_mode(regs) (((regs)->sstatus & SR_SPP) == 0)
+#define MAX_REG_OFFSET offsetof(struct pt_regs, orig_a0)
/* Helpers for working with the instruction pointer */ static inline unsigned long instruction_pointer(struct pt_regs *regs) @@ -85,6 +87,12 @@ static inline void user_stack_pointer_set(struct pt_regs *regs, regs->sp = val; }
+/* Valid only for Kernel mode traps. */ +static inline unsigned long kernel_stack_pointer(struct pt_regs *regs) +{ + return regs->sp; +} + /* Helpers for working with the frame pointer */ static inline unsigned long frame_pointer(struct pt_regs *regs) { @@ -101,6 +109,28 @@ static inline unsigned long regs_return_value(struct pt_regs *regs) return regs->a0; }
+int regs_query_register_offset(const char *name); +unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, + unsigned int n); + +/** + * regs_get_register() - get register value from its offset + * @regs: pt_regs from which register value is gotten + * @offset: offset of the register. + * + * regs_get_register() returns the value from @regs of a register + * identified by @offset. The @offset is the offset of the register + * in struct pt_regs. If @offset is bigger than MAX_REG_OFFSET, this + * returns 0. + */ +static inline unsigned long regs_get_register(struct pt_regs *regs, + unsigned int offset) +{ + if (unlikely(offset > MAX_REG_OFFSET)) + return 0; + + return *(unsigned long *)((unsigned long)regs + offset); +} #endif /* __ASSEMBLY__ */
#endif /* _ASM_RISCV_PTRACE_H */ diff --git a/arch/riscv/kernel/ptrace.c b/arch/riscv/kernel/ptrace.c index 1252113ef8b2..5076b30fe18b 100644 --- a/arch/riscv/kernel/ptrace.c +++ b/arch/riscv/kernel/ptrace.c @@ -125,6 +125,105 @@ const struct user_regset_view *task_user_regset_view(struct task_struct *task) return &riscv_user_native_view; }
+struct pt_regs_offset { + const char *name; + int offset; +}; + +#define REG_OFFSET_NAME(r) {.name = #r, .offset = offsetof(struct pt_regs, r)} +#define REG_OFFSET_END {.name = NULL, .offset = 0} + +static const struct pt_regs_offset regoffset_table[] = { + REG_OFFSET_NAME(sepc), + REG_OFFSET_NAME(ra), + REG_OFFSET_NAME(sp), + REG_OFFSET_NAME(gp), + REG_OFFSET_NAME(tp), + REG_OFFSET_NAME(t0), + REG_OFFSET_NAME(t1), + REG_OFFSET_NAME(t2), + REG_OFFSET_NAME(s0), + REG_OFFSET_NAME(s1), + REG_OFFSET_NAME(a0), + REG_OFFSET_NAME(a1), + REG_OFFSET_NAME(a2), + REG_OFFSET_NAME(a3), + REG_OFFSET_NAME(a4), + REG_OFFSET_NAME(a5), + REG_OFFSET_NAME(a6), + REG_OFFSET_NAME(a7), + REG_OFFSET_NAME(s2), + REG_OFFSET_NAME(s3), + REG_OFFSET_NAME(s4), + REG_OFFSET_NAME(s5), + REG_OFFSET_NAME(s6), + REG_OFFSET_NAME(s7), + REG_OFFSET_NAME(s8), + REG_OFFSET_NAME(s9), + REG_OFFSET_NAME(s10), + REG_OFFSET_NAME(s11), + REG_OFFSET_NAME(t3), + REG_OFFSET_NAME(t4), + REG_OFFSET_NAME(t5), + REG_OFFSET_NAME(t6), + REG_OFFSET_NAME(sstatus), + REG_OFFSET_NAME(sbadaddr), + REG_OFFSET_NAME(scause), + REG_OFFSET_NAME(orig_a0), + REG_OFFSET_END, +}; + +/** + * regs_query_register_offset() - query register offset from its name + * @name: the name of a register + * + * regs_query_register_offset() returns the offset of a register in struct + * pt_regs from its name. If the name is invalid, this returns -EINVAL; + */ +int regs_query_register_offset(const char *name) +{ + const struct pt_regs_offset *roff; + + for (roff = regoffset_table; roff->name; roff++) + if (!strcmp(roff->name, name)) + return roff->offset; + return -EINVAL; +} + +/** + * regs_within_kernel_stack() - check the address in the stack + * @regs: pt_regs which contains kernel stack pointer. + * @addr: address which is checked. + * + * regs_within_kernel_stack() checks @addr is within the kernel stack page(s). + * If @addr is within the kernel stack, it returns true. If not, returns false. + */ +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)); +} + +/** + * regs_get_kernel_stack_nth() - get Nth entry of the stack + * @regs: pt_regs which contains kernel stack pointer. + * @n: stack entry number. + * + * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which + * is specified by @regs. If the @n th entry is NOT in the kernel stack, + * this returns 0. + */ +unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n) +{ + unsigned long *addr = (unsigned long *)kernel_stack_pointer(regs); + + addr += n; + if (regs_within_kernel_stack(regs, (unsigned long)addr)) + return *addr; + else + return 0; +} + void ptrace_disable(struct task_struct *child) { clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
On Fri, Nov 22, 2019 at 6:32 AM Paul Walmsley paul.walmsley@sifive.com wrote:
On Thu, 21 Nov 2019, Paul Walmsley wrote:
As I understand it, this patch hasn't been signed off on by Patrick. I've sent him an E-mail asking him whether he's willing to add his Signed-off-by:, but haven't heard back from it.
From our discussions, I understand that this patch is based partially on some of his earlier, public, kprobes work. In lieu of any response from Patrick, could you please resend this patch and just note in the commit description that it's partially based on one of his patches, add a Link: line that points to the URL of the patch that it's partially based on, and replace the Signed-off-by: with a Co-developed-by: or something similar?
OK - just looked at the patches more closely, and I think I see what's going on here. This patch looks like a rebased version of this patch:
https://lore.kernel.org/linux-riscv/20181113195804.22825-2-me@packi.ch/
So let's just plan to use an updated version of Patrick's original (below). Please let me know if you have any comments on it or if I missed something -
- Paul
Dear Paul, Due to the rule of mail classification, I do not find this mail in time. I am sorry for that. I think it is good for me.
Thanks and regards Vincent
From: Patrick Stählin me@packi.ch Date: Tue, 13 Nov 2018 20:58:03 +0100 Subject: [PATCH] RISC-V: Implement ptrace regs and stack API MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit
Needed for kprobes support. Copied and adapted from arm64 code.
Signed-off-by: Patrick Stählin me@packi.ch [paul.walmsley@sifive.com: updated to apply; fixed checkpatch issues; fixed regs_get_register() kerneldoc] Cc: Vincent Chen vincent.chen@sifive.com Link: https://lore.kernel.org/linux-riscv/20181113195803.CjtBCsUcG9czwiqmPBGKUjvl5... Link: https://lore.kernel.org/linux-riscv/1572919114-3886-1-git-send-email-vincent... Signed-off-by: Paul Walmsley paul.walmsley@sifive.com
arch/riscv/Kconfig | 1 + arch/riscv/include/asm/ptrace.h | 30 ++++++++++ arch/riscv/kernel/ptrace.c | 99 +++++++++++++++++++++++++++++++++ 3 files changed, 130 insertions(+)
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 8eebbc8860bb..d5bbf4223fd2 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -61,6 +61,7 @@ config RISCV select SPARSEMEM_STATIC if 32BIT select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU select HAVE_ARCH_MMAP_RND_BITS
select HAVE_REGS_AND_STACK_ACCESS_APIconfig ARCH_MMAP_RND_BITS_MIN default 18 if 64BIT diff --git a/arch/riscv/include/asm/ptrace.h b/arch/riscv/include/asm/ptrace.h index d48d1e13973c..50d37b123a61 100644 --- a/arch/riscv/include/asm/ptrace.h +++ b/arch/riscv/include/asm/ptrace.h @@ -8,6 +8,7 @@
#include <uapi/asm/ptrace.h> #include <asm/csr.h> +#include <linux/compiler.h>
#ifndef __ASSEMBLY__
@@ -60,6 +61,7 @@ struct pt_regs {
#define user_mode(regs) (((regs)->sstatus & SR_SPP) == 0)
+#define MAX_REG_OFFSET offsetof(struct pt_regs, orig_a0)
/* Helpers for working with the instruction pointer */ static inline unsigned long instruction_pointer(struct pt_regs *regs) @@ -85,6 +87,12 @@ static inline void user_stack_pointer_set(struct pt_regs *regs, regs->sp = val; }
+/* Valid only for Kernel mode traps. */ +static inline unsigned long kernel_stack_pointer(struct pt_regs *regs) +{
return regs->sp;+}
/* Helpers for working with the frame pointer */ static inline unsigned long frame_pointer(struct pt_regs *regs) { @@ -101,6 +109,28 @@ static inline unsigned long regs_return_value(struct pt_regs *regs) return regs->a0; }
+int regs_query_register_offset(const char *name); +unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs,
unsigned int n);+/**
- regs_get_register() - get register value from its offset
- @regs: pt_regs from which register value is gotten
- @offset: offset of the register.
- regs_get_register() returns the value from @regs of a register
- identified by @offset. The @offset is the offset of the register
- in struct pt_regs. If @offset is bigger than MAX_REG_OFFSET, this
- returns 0.
- */
+static inline unsigned long regs_get_register(struct pt_regs *regs,
unsigned int offset)+{
if (unlikely(offset > MAX_REG_OFFSET))return 0;return *(unsigned long *)((unsigned long)regs + offset);+} #endif /* __ASSEMBLY__ */
#endif /* _ASM_RISCV_PTRACE_H */ diff --git a/arch/riscv/kernel/ptrace.c b/arch/riscv/kernel/ptrace.c index 1252113ef8b2..5076b30fe18b 100644 --- a/arch/riscv/kernel/ptrace.c +++ b/arch/riscv/kernel/ptrace.c @@ -125,6 +125,105 @@ const struct user_regset_view *task_user_regset_view(struct task_struct *task) return &riscv_user_native_view; }
+struct pt_regs_offset {
const char *name;int offset;+};
+#define REG_OFFSET_NAME(r) {.name = #r, .offset = offsetof(struct pt_regs, r)} +#define REG_OFFSET_END {.name = NULL, .offset = 0}
+static const struct pt_regs_offset regoffset_table[] = {
REG_OFFSET_NAME(sepc),REG_OFFSET_NAME(ra),REG_OFFSET_NAME(sp),REG_OFFSET_NAME(gp),REG_OFFSET_NAME(tp),REG_OFFSET_NAME(t0),REG_OFFSET_NAME(t1),REG_OFFSET_NAME(t2),REG_OFFSET_NAME(s0),REG_OFFSET_NAME(s1),REG_OFFSET_NAME(a0),REG_OFFSET_NAME(a1),REG_OFFSET_NAME(a2),REG_OFFSET_NAME(a3),REG_OFFSET_NAME(a4),REG_OFFSET_NAME(a5),REG_OFFSET_NAME(a6),REG_OFFSET_NAME(a7),REG_OFFSET_NAME(s2),REG_OFFSET_NAME(s3),REG_OFFSET_NAME(s4),REG_OFFSET_NAME(s5),REG_OFFSET_NAME(s6),REG_OFFSET_NAME(s7),REG_OFFSET_NAME(s8),REG_OFFSET_NAME(s9),REG_OFFSET_NAME(s10),REG_OFFSET_NAME(s11),REG_OFFSET_NAME(t3),REG_OFFSET_NAME(t4),REG_OFFSET_NAME(t5),REG_OFFSET_NAME(t6),REG_OFFSET_NAME(sstatus),REG_OFFSET_NAME(sbadaddr),REG_OFFSET_NAME(scause),REG_OFFSET_NAME(orig_a0),REG_OFFSET_END,+};
+/**
- regs_query_register_offset() - query register offset from its name
- @name: the name of a register
- regs_query_register_offset() returns the offset of a register in struct
- pt_regs from its name. If the name is invalid, this returns -EINVAL;
- */
+int regs_query_register_offset(const char *name) +{
const struct pt_regs_offset *roff;for (roff = regoffset_table; roff->name; roff++)if (!strcmp(roff->name, name))return roff->offset;return -EINVAL;+}
+/**
- regs_within_kernel_stack() - check the address in the stack
- @regs: pt_regs which contains kernel stack pointer.
- @addr: address which is checked.
- regs_within_kernel_stack() checks @addr is within the kernel stack page(s).
- If @addr is within the kernel stack, it returns true. If not, returns false.
- */
+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));+}
+/**
- regs_get_kernel_stack_nth() - get Nth entry of the stack
- @regs: pt_regs which contains kernel stack pointer.
- @n: stack entry number.
- regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
- is specified by @regs. If the @n th entry is NOT in the kernel stack,
- this returns 0.
- */
+unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n) +{
unsigned long *addr = (unsigned long *)kernel_stack_pointer(regs);addr += n;if (regs_within_kernel_stack(regs, (unsigned long)addr))return *addr;elsereturn 0;+}
void ptrace_disable(struct task_struct *child) { clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); -- 2.24.0.rc0
Add calls to rseq_signal_deliver(), rseq_handle_notify_resume() and rseq_syscall() to introduce RSEQ support.
1. Call the rseq_handle_notify_resume() function on return to userspace if TIF_NOTIFY_RESUME thread flag is set.
2. Call the rseq_signal_deliver() function to fixup on the pre-signal frame when a signal is delivered on top of a restartable sequence critical section.
3. Check that system calls are not invoked from within rseq critical sections by invoking rseq_signal() from ret_from_syscall(). With CONFIG_DEBUG_RSEQ, such behavior results in termination of the process with SIGSEGV.
Signed-off-by: Vincent Chen vincent.chen@sifive.com --- arch/riscv/Kconfig | 1 + arch/riscv/kernel/entry.S | 4 ++++ arch/riscv/kernel/signal.c | 3 +++ 3 files changed, 8 insertions(+)
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index d5bbf4223fd2..58759a4f8dff 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -62,6 +62,7 @@ config RISCV select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU select HAVE_ARCH_MMAP_RND_BITS select HAVE_REGS_AND_STACK_ACCESS_API + select HAVE_RSEQ
config ARCH_MMAP_RND_BITS_MIN default 18 if 64BIT diff --git a/arch/riscv/kernel/entry.S b/arch/riscv/kernel/entry.S index 8ca479831142..00e9eaa02969 100644 --- a/arch/riscv/kernel/entry.S +++ b/arch/riscv/kernel/entry.S @@ -212,6 +212,10 @@ ENTRY(handle_exception) handle_syscall: /* save the initial A0 value (needed in signal handlers) */ REG_S a0, PT_ORIG_A0(sp) +#ifdef CONFIG_RSEQ_DEBUG + move a0, sp + call rseq_syscall +#endif /* * Advance SEPC to avoid executing the original * scall instruction on sret diff --git a/arch/riscv/kernel/signal.c b/arch/riscv/kernel/signal.c index d0f6f212f5df..f2f6017f92d0 100644 --- a/arch/riscv/kernel/signal.c +++ b/arch/riscv/kernel/signal.c @@ -219,6 +219,8 @@ static void handle_signal(struct ksignal *ksig, struct pt_regs *regs) sigset_t *oldset = sigmask_to_save(); int ret;
+ rseq_signal_deliver(ksig, regs); + /* Are we from a system call? */ if (regs->scause == EXC_SYSCALL) { /* Avoid additional syscall restarting via ret_from_exception */ @@ -302,5 +304,6 @@ asmlinkage __visible void do_notify_resume(struct pt_regs *regs, if (thread_info_flags & _TIF_NOTIFY_RESUME) { clear_thread_flag(TIF_NOTIFY_RESUME); tracehook_notify_resume(regs); + rseq_handle_notify_resume(NULL, regs); } }
Add support for risc-v in the rseq selftests, which covers both 64-bit and 32-bit ISA with little endian mode.
Signed-off-by: Vincent Chen vincent.chen@sifive.com --- tools/testing/selftests/rseq/param_test.c | 23 ++ tools/testing/selftests/rseq/rseq-riscv.h | 622 ++++++++++++++++++++++++++++++ tools/testing/selftests/rseq/rseq.h | 2 + 3 files changed, 647 insertions(+) create mode 100644 tools/testing/selftests/rseq/rseq-riscv.h
diff --git a/tools/testing/selftests/rseq/param_test.c b/tools/testing/selftests/rseq/param_test.c index eec2663261f2..5e4e7e8fb9c2 100644 --- a/tools/testing/selftests/rseq/param_test.c +++ b/tools/testing/selftests/rseq/param_test.c @@ -205,6 +205,29 @@ unsigned int yield_mod_cnt, nr_abort; "addiu " INJECT_ASM_REG ", -1\n\t" \ "bnez " INJECT_ASM_REG ", 222b\n\t" \ "333:\n\t" +#elif defined(__riscv) + +#define RSEQ_INJECT_INPUT \ + , [loop_cnt_1]"m"(loop_cnt[1]) \ + , [loop_cnt_2]"m"(loop_cnt[2]) \ + , [loop_cnt_3]"m"(loop_cnt[3]) \ + , [loop_cnt_4]"m"(loop_cnt[4]) \ + , [loop_cnt_5]"m"(loop_cnt[5]) \ + , [loop_cnt_6]"m"(loop_cnt[6]) + +#define INJECT_ASM_REG "t1" + +#define RSEQ_INJECT_CLOBBER \ + , INJECT_ASM_REG + +#define RSEQ_INJECT_ASM(n) \ + "lw " INJECT_ASM_REG ", %[loop_cnt_" #n "]\n\t" \ + "beqz " INJECT_ASM_REG ", 333f\n\t" \ + "222:\n\t" \ + "addi " INJECT_ASM_REG "," INJECT_ASM_REG ", -1\n\t" \ + "bnez " INJECT_ASM_REG ", 222b\n\t" \ + "333:\n\t" +
#else #error unsupported target diff --git a/tools/testing/selftests/rseq/rseq-riscv.h b/tools/testing/selftests/rseq/rseq-riscv.h new file mode 100644 index 000000000000..56b47db4a9a4 --- /dev/null +++ b/tools/testing/selftests/rseq/rseq-riscv.h @@ -0,0 +1,622 @@ +/* SPDX-License-Identifier: LGPL-2.1 OR MIT */ +/* + * Select the instruction "csrw mhartid, x0" as the RSEQ_SIG. Unlike + * other architecture, the ebreak instruction has no immediate field for + * distinguishing purposes. Hence, ebreak is not suitable as RSEQ_SIG. + * "csrw mhartid, x0" can also satisfy the RSEQ requirement because it + * is an uncommon instruction and will raise an illegal instruction + * exception when executed in all modes. + */ + +#if __ORDER_LITTLE_ENDIAN__ == 1234 +#define RSEQ_SIG 0xf1401073 /* csrr mhartid, x0 */ +#else +#error "Currently, RSEQ only supports Little-Endian version" +#endif + +#if __riscv_xlen == 64 +#define __REG_SEL(a, b) a +#elif __riscv_xlen == 32 +#define __REG_SEL(a, b) b +#endif + +#define REG_L __REG_SEL("ld ", "lw ") +#define REG_S __REG_SEL("sd ", "sw ") + +#define RISCV_FENCE(p, s) \ + __asm__ __volatile__ ("fence " #p "," #s : : : "memory") +#define rseq_smp_mb() RISCV_FENCE(rw, rw) +#define rseq_smp_rmb() RISCV_FENCE(r, r) +#define rseq_smp_wmb() RISCV_FENCE(w, w) +#define RSEQ_ASM_TMP_REG_1 "t6" +#define RSEQ_ASM_TMP_REG_2 "t5" +#define RSEQ_ASM_TMP_REG_3 "t4" +#define RSEQ_ASM_TMP_REG_4 "t3" + +#define rseq_smp_load_acquire(p) \ +__extension__ ({ \ + __typeof(*p) ____p1 = RSEQ_READ_ONCE(*p); \ + RISCV_FENCE(r, rw) \ + ____p1; \ +}) + +#define rseq_smp_acquire__after_ctrl_dep() rseq_smp_rmb() + +#define rseq_smp_store_release(p, v) \ +do { \ + RISCV_FENCE(rw, w); \ + RSEQ_WRITE_ONCE(*p, v); \ +} while (0) + + +#ifdef RSEQ_SKIP_FASTPATH +#include "rseq-skip.h" +#else /* !RSEQ_SKIP_FASTPATH */ + +#define __RSEQ_ASM_DEFINE_TABLE(label, version, flags, start_ip, \ + post_commit_offset, abort_ip) \ + ".pushsection __rseq_cs, "aw"\n" \ + ".balign 32\n" \ + __rseq_str(label) ":\n" \ + ".long " __rseq_str(version) ", " __rseq_str(flags) "\n" \ + ".quad " __rseq_str(start_ip) ", " \ + __rseq_str(post_commit_offset) ", " \ + __rseq_str(abort_ip) "\n" \ + ".popsection\n\t" \ + ".pushsection __rseq_cs_ptr_array, "aw"\n" \ + ".quad " __rseq_str(label) "b\n" \ + ".popsection\n" + +#define RSEQ_ASM_DEFINE_TABLE(label, start_ip, post_commit_ip, abort_ip) \ + __RSEQ_ASM_DEFINE_TABLE(label, 0x0, 0x0, start_ip, \ + (post_commit_ip - start_ip), abort_ip) + + +/* + * Exit points of a rseq critical section consist of all instructions outside + * of the critical section where a critical section can either branch to or + * reach through the normal course of its execution. The abort IP and the + * post-commit IP are already part of the __rseq_cs section and should not be + * explicitly defined as additional exit points. Knowing all exit points is + * useful to assist debuggers stepping over the critical section. + */ +#define RSEQ_ASM_DEFINE_EXIT_POINT(start_ip, exit_ip) \ + ".pushsection __rseq_exit_point_array, "aw"\n" \ + ".quad " __rseq_str(start_ip) ", " __rseq_str(exit_ip) "\n" \ + ".popsection\n" + +#define RSEQ_ASM_STORE_RSEQ_CS(label, cs_label, rseq_cs) \ + RSEQ_INJECT_ASM(1) \ + "la "RSEQ_ASM_TMP_REG_1 ", " __rseq_str(cs_label) "\n" \ + REG_S RSEQ_ASM_TMP_REG_1 ", %[" __rseq_str(rseq_cs) "]\n" \ + __rseq_str(label) ":\n" + +#define RSEQ_ASM_DEFINE_ABORT(label, abort_label) \ + "j 222f\n" \ + ".balign 4\n" \ + ".long " __rseq_str(RSEQ_SIG) "\n" \ + __rseq_str(label) ":\n" \ + "j %l[" __rseq_str(abort_label) "]\n" \ + "222:\n" + +#define RSEQ_ASM_OP_STORE(value, var) \ + REG_S "%[" __rseq_str(value) "], %[" __rseq_str(var) "]\n" + +#define RSEQ_ASM_OP_CMPEQ(var, expect, label) \ + REG_L RSEQ_ASM_TMP_REG_1 ", %[" __rseq_str(var) "]\n" \ + "bne "RSEQ_ASM_TMP_REG_1 ", %[" __rseq_str(expect) "] ," \ + __rseq_str(label) "\n" + +#define RSEQ_ASM_OP_CMPEQ32(var, expect, label) \ + "lw "RSEQ_ASM_TMP_REG_1 ", %[" __rseq_str(var) "]\n" \ + "bne "RSEQ_ASM_TMP_REG_1 ", %[" __rseq_str(expect) "] ," \ + __rseq_str(label) "\n" + +#define RSEQ_ASM_OP_CMPNE(var, expect, label) \ + REG_L RSEQ_ASM_TMP_REG_1 ", %[" __rseq_str(var) "]\n" \ + "beq "RSEQ_ASM_TMP_REG_1 ", %[" __rseq_str(expect) "] ," \ + __rseq_str(label) "\n" + +#define RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, label) \ + RSEQ_INJECT_ASM(2) \ + RSEQ_ASM_OP_CMPEQ32(current_cpu_id, cpu_id, label) + +#define RSEQ_ASM_OP_R_LOAD(var) \ + REG_L RSEQ_ASM_TMP_REG_1 ", %[" __rseq_str(var) "]\n" + +#define RSEQ_ASM_OP_R_STORE(var) \ + REG_S RSEQ_ASM_TMP_REG_1 ", %[" __rseq_str(var) "]\n" + +#define RSEQ_ASM_OP_R_LOAD_OFF(offset) \ + "add "RSEQ_ASM_TMP_REG_1 ", %[" __rseq_str(offset) "], " \ + RSEQ_ASM_TMP_REG_1 "\n" \ + REG_L RSEQ_ASM_TMP_REG_1 ", (" RSEQ_ASM_TMP_REG_1 ")\n" + +#define RSEQ_ASM_OP_R_ADD(count) \ + "add "RSEQ_ASM_TMP_REG_1 ", " RSEQ_ASM_TMP_REG_1 \ + ", %[" __rseq_str(count) "]\n" + +#define RSEQ_ASM_OP_FINAL_STORE(value, var, post_commit_label) \ + RSEQ_ASM_OP_STORE(value, var) \ + __rseq_str(post_commit_label) ":\n" + +#define RSEQ_ASM_OP_FINAL_STORE_RELEASE(value, var, post_commit_label) \ + "fence rw, w\n" \ + RSEQ_ASM_OP_STORE(value, var) \ + __rseq_str(post_commit_label) ":\n" + +#define RSEQ_ASM_OP_R_FINAL_STORE(var, post_commit_label) \ + REG_S RSEQ_ASM_TMP_REG_1 ", %[" __rseq_str(var) "]\n" \ + __rseq_str(post_commit_label) ":\n" + +#define RSEQ_ASM_OP_R_BAD_MEMCPY(dst, src, len) \ + "beqz %[" __rseq_str(len) "], 333f\n" \ + "mv " RSEQ_ASM_TMP_REG_1 ", %[" __rseq_str(len) "]\n" \ + "mv " RSEQ_ASM_TMP_REG_2 ", %[" __rseq_str(src) "]\n" \ + "mv " RSEQ_ASM_TMP_REG_3 ", %[" __rseq_str(dst) "]\n" \ + "222:\n" \ + "lb " RSEQ_ASM_TMP_REG_4 ", 0(" RSEQ_ASM_TMP_REG_2 ")\n" \ + "sb " RSEQ_ASM_TMP_REG_4 ", 0(" RSEQ_ASM_TMP_REG_3 ")\n" \ + "addi " RSEQ_ASM_TMP_REG_1 ", " RSEQ_ASM_TMP_REG_1 ", -1\n" \ + "addi " RSEQ_ASM_TMP_REG_2 ", " RSEQ_ASM_TMP_REG_2 ", 1\n" \ + "addi " RSEQ_ASM_TMP_REG_3 ", " RSEQ_ASM_TMP_REG_3 ", 1\n" \ + "bnez " RSEQ_ASM_TMP_REG_1 ", 222b\n" \ + "333:\n" + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_storev(intptr_t *v, intptr_t expect, intptr_t newv, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(1, 2f, 3f, 4f) + RSEQ_ASM_DEFINE_EXIT_POINT(2f, %l[cmpfail]) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_DEFINE_EXIT_POINT(2f, %l[error1]) + RSEQ_ASM_DEFINE_EXIT_POINT(2f, %l[error2]) +#endif + RSEQ_ASM_STORE_RSEQ_CS(2, 1b, rseq_cs) + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) + RSEQ_ASM_OP_CMPEQ(v, expect, %l[cmpfail]) + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1]) + RSEQ_ASM_OP_CMPEQ(v, expect, %l[error2]) +#endif + RSEQ_ASM_OP_FINAL_STORE(newv, v, 3) + RSEQ_INJECT_ASM(5) + RSEQ_ASM_DEFINE_ABORT(4, abort) + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (__rseq_abi.cpu_id), + [rseq_cs] "m" (__rseq_abi.rseq_cs), + [v] "m" (*v), + [expect] "r" (expect), + [newv] "r" (newv) + RSEQ_INJECT_INPUT + : "memory", RSEQ_ASM_TMP_REG_1 + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + + return 0; +abort: + RSEQ_INJECT_FAILED + return -1; +cmpfail: + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_bug("cpu_id comparison failed"); +error2: + rseq_bug("expected value comparison failed"); +#endif +} + +static inline __attribute__((always_inline)) +int rseq_cmpnev_storeoffp_load(intptr_t *v, intptr_t expectnot, + off_t voffp, intptr_t *load, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(1, 2f, 3f, 4f) + RSEQ_ASM_DEFINE_EXIT_POINT(2f, %l[cmpfail]) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_DEFINE_EXIT_POINT(2f, %l[error1]) + RSEQ_ASM_DEFINE_EXIT_POINT(2f, %l[error2]) +#endif + RSEQ_ASM_STORE_RSEQ_CS(2, 1b, rseq_cs) + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) + RSEQ_ASM_OP_CMPNE(v, expectnot, %l[cmpfail]) + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1]) + RSEQ_ASM_OP_CMPNE(v, expectnot, %l[error2]) +#endif + RSEQ_ASM_OP_R_LOAD(v) + RSEQ_ASM_OP_R_STORE(load) + RSEQ_ASM_OP_R_LOAD_OFF(voffp) + RSEQ_ASM_OP_R_FINAL_STORE(v, 3) + RSEQ_INJECT_ASM(5) + RSEQ_ASM_DEFINE_ABORT(4, abort) + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (__rseq_abi.cpu_id), + [rseq_cs] "m" (__rseq_abi.rseq_cs), + [v] "m" (*v), + [expectnot] "r" (expectnot), + [load] "m" (*load), + [voffp] "r" (voffp) + RSEQ_INJECT_INPUT + : "memory", RSEQ_ASM_TMP_REG_1 + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + return 0; +abort: + RSEQ_INJECT_FAILED + return -1; +cmpfail: + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_bug("cpu_id comparison failed"); +error2: + rseq_bug("expected value comparison failed"); +#endif +} + +static inline __attribute__((always_inline)) +int rseq_addv(intptr_t *v, intptr_t count, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(1, 2f, 3f, 4f) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_DEFINE_EXIT_POINT(2f, %l[error1]) +#endif + RSEQ_ASM_STORE_RSEQ_CS(2, 1b, rseq_cs) + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1]) +#endif + RSEQ_ASM_OP_R_LOAD(v) + RSEQ_ASM_OP_R_ADD(count) + RSEQ_ASM_OP_R_FINAL_STORE(v, 3) + RSEQ_INJECT_ASM(4) + RSEQ_ASM_DEFINE_ABORT(4, abort) + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (__rseq_abi.cpu_id), + [rseq_cs] "m" (__rseq_abi.rseq_cs), + [v] "m" (*v), + [count] "r" (count) + RSEQ_INJECT_INPUT + : "memory", RSEQ_ASM_TMP_REG_1 + : abort +#ifdef RSEQ_COMPARE_TWICE + , error1 +#endif + ); + return 0; +abort: + RSEQ_INJECT_FAILED + return -1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_bug("cpu_id comparison failed"); +#endif +} + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_trystorev_storev(intptr_t *v, intptr_t expect, + intptr_t *v2, intptr_t newv2, + intptr_t newv, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(1, 2f, 3f, 4f) + RSEQ_ASM_DEFINE_EXIT_POINT(2f, %l[cmpfail]) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_DEFINE_EXIT_POINT(2f, %l[error1]) + RSEQ_ASM_DEFINE_EXIT_POINT(2f, %l[error2]) +#endif + RSEQ_ASM_STORE_RSEQ_CS(2, 1b, rseq_cs) + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) + RSEQ_ASM_OP_CMPEQ(v, expect, %l[cmpfail]) + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1]) + RSEQ_ASM_OP_CMPEQ(v, expect, %l[error2]) +#endif + RSEQ_ASM_OP_STORE(newv2, v2) + RSEQ_INJECT_ASM(5) + RSEQ_ASM_OP_FINAL_STORE(newv, v, 3) + RSEQ_INJECT_ASM(6) + RSEQ_ASM_DEFINE_ABORT(4, abort) + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (__rseq_abi.cpu_id), + [rseq_cs] "m" (__rseq_abi.rseq_cs), + [expect] "r" (expect), + [v] "m" (*v), + [newv] "r" (newv), + [v2] "m" (*v2), + [newv2] "r" (newv2) + RSEQ_INJECT_INPUT + : "memory", RSEQ_ASM_TMP_REG_1 + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + + return 0; +abort: + RSEQ_INJECT_FAILED + return -1; +cmpfail: + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_bug("cpu_id comparison failed"); +error2: + rseq_bug("expected value comparison failed"); +#endif +} + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_trystorev_storev_release(intptr_t *v, intptr_t expect, + intptr_t *v2, intptr_t newv2, + intptr_t newv, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(1, 2f, 3f, 4f) + RSEQ_ASM_DEFINE_EXIT_POINT(2f, %l[cmpfail]) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_DEFINE_EXIT_POINT(2f, %l[error1]) + RSEQ_ASM_DEFINE_EXIT_POINT(2f, %l[error2]) +#endif + RSEQ_ASM_STORE_RSEQ_CS(2, 1b, rseq_cs) + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) + RSEQ_ASM_OP_CMPEQ(v, expect, %l[cmpfail]) + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1]) + RSEQ_ASM_OP_CMPEQ(v, expect, %l[error2]) +#endif + RSEQ_ASM_OP_STORE(newv2, v2) + RSEQ_INJECT_ASM(5) + RSEQ_ASM_OP_FINAL_STORE_RELEASE(newv, v, 3) + RSEQ_INJECT_ASM(6) + RSEQ_ASM_DEFINE_ABORT(4, abort) + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (__rseq_abi.cpu_id), + [rseq_cs] "m" (__rseq_abi.rseq_cs), + [expect] "r" (expect), + [v] "m" (*v), + [newv] "r" (newv), + [v2] "m" (*v2), + [newv2] "r" (newv2) + RSEQ_INJECT_INPUT + : "memory", RSEQ_ASM_TMP_REG_1 + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + + return 0; +abort: + RSEQ_INJECT_FAILED + return -1; +cmpfail: + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_bug("cpu_id comparison failed"); +error2: + rseq_bug("expected value comparison failed"); +#endif +} + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_cmpeqv_storev(intptr_t *v, intptr_t expect, + intptr_t *v2, intptr_t expect2, + intptr_t newv, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(1, 2f, 3f, 4f) + RSEQ_ASM_DEFINE_EXIT_POINT(2f, %l[cmpfail]) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_DEFINE_EXIT_POINT(2f, %l[error1]) + RSEQ_ASM_DEFINE_EXIT_POINT(2f, %l[error2]) + RSEQ_ASM_DEFINE_EXIT_POINT(2f, %l[error3]) +#endif + RSEQ_ASM_STORE_RSEQ_CS(2, 1b, rseq_cs) + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) + RSEQ_ASM_OP_CMPEQ(v, expect, %l[cmpfail]) + RSEQ_INJECT_ASM(4) + RSEQ_ASM_OP_CMPEQ(v2, expect2, %l[cmpfail]) + RSEQ_INJECT_ASM(5) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1]) + RSEQ_ASM_OP_CMPEQ(v, expect, %l[error2]) + RSEQ_ASM_OP_CMPEQ(v2, expect2, %l[error3]) +#endif + RSEQ_ASM_OP_FINAL_STORE(newv, v, 3) + RSEQ_INJECT_ASM(6) + RSEQ_ASM_DEFINE_ABORT(4, abort) + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (__rseq_abi.cpu_id), + [rseq_cs] "m" (__rseq_abi.rseq_cs), + [v] "m" (*v), + [expect] "r" (expect), + [v2] "m" (*v2), + [expect2] "r" (expect2), + [newv] "r" (newv) + RSEQ_INJECT_INPUT + : "memory", RSEQ_ASM_TMP_REG_1 + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2, error3 +#endif + ); + + return 0; +abort: + RSEQ_INJECT_FAILED + return -1; +cmpfail: + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_bug("cpu_id comparison failed"); +error2: + rseq_bug("expected value comparison failed"); +error3: + rseq_bug("2nd expected value comparison failed"); +#endif +} + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_trymemcpy_storev(intptr_t *v, intptr_t expect, + void *dst, void *src, size_t len, + intptr_t newv, int cpu) +{ + RSEQ_INJECT_C(9) + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(1, 2f, 3f, 4f) + RSEQ_ASM_DEFINE_EXIT_POINT(2f, %l[cmpfail]) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_DEFINE_EXIT_POINT(2f, %l[error1]) + RSEQ_ASM_DEFINE_EXIT_POINT(2f, %l[error2]) +#endif + RSEQ_ASM_STORE_RSEQ_CS(2, 1b, rseq_cs) + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) + RSEQ_ASM_OP_CMPEQ(v, expect, %l[cmpfail]) + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1]) + RSEQ_ASM_OP_CMPEQ(v, expect, %l[error2]) +#endif + RSEQ_ASM_OP_R_BAD_MEMCPY(dst, src, len) + RSEQ_INJECT_ASM(5) + RSEQ_ASM_OP_FINAL_STORE(newv, v, 3) + RSEQ_INJECT_ASM(6) + RSEQ_ASM_DEFINE_ABORT(4, abort) + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (__rseq_abi.cpu_id), + [rseq_cs] "m" (__rseq_abi.rseq_cs), + [expect] "r" (expect), + [v] "m" (*v), + [newv] "r" (newv), + [dst] "r" (dst), + [src] "r" (src), + [len] "r" (len) + RSEQ_INJECT_INPUT + : "memory", RSEQ_ASM_TMP_REG_1, RSEQ_ASM_TMP_REG_2, + RSEQ_ASM_TMP_REG_3, RSEQ_ASM_TMP_REG_4 + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + + return 0; +abort: + RSEQ_INJECT_FAILED + return -1; +cmpfail: + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_bug("cpu_id comparison failed"); +error2: + rseq_bug("expected value comparison failed"); +#endif +} + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_trymemcpy_storev_release(intptr_t *v, intptr_t expect, + void *dst, void *src, size_t len, + intptr_t newv, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(1, 2f, 3f, 4f) + RSEQ_ASM_DEFINE_EXIT_POINT(2f, %l[cmpfail]) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_DEFINE_EXIT_POINT(2f, %l[error1]) + RSEQ_ASM_DEFINE_EXIT_POINT(2f, %l[error2]) +#endif + RSEQ_ASM_STORE_RSEQ_CS(2, 1b, rseq_cs) + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) + RSEQ_ASM_OP_CMPEQ(v, expect, %l[cmpfail]) + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1]) + RSEQ_ASM_OP_CMPEQ(v, expect, %l[error2]) +#endif + RSEQ_ASM_OP_R_BAD_MEMCPY(dst, src, len) + RSEQ_INJECT_ASM(5) + RSEQ_ASM_OP_FINAL_STORE_RELEASE(newv, v, 3) + RSEQ_INJECT_ASM(6) + RSEQ_ASM_DEFINE_ABORT(4, abort) + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (__rseq_abi.cpu_id), + [rseq_cs] "m" (__rseq_abi.rseq_cs), + [expect] "r" (expect), + [v] "m" (*v), + [newv] "r" (newv), + [dst] "r" (dst), + [src] "r" (src), + [len] "r" (len) + RSEQ_INJECT_INPUT + : "memory", RSEQ_ASM_TMP_REG_1, RSEQ_ASM_TMP_REG_2, + RSEQ_ASM_TMP_REG_3, RSEQ_ASM_TMP_REG_4 + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + + return 0; +abort: + RSEQ_INJECT_FAILED + return -1; +cmpfail: + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_bug("cpu_id comparison failed"); +error2: + rseq_bug("expected value comparison failed"); +#endif +} + +#endif /* !RSEQ_SKIP_FASTPATH */ diff --git a/tools/testing/selftests/rseq/rseq.h b/tools/testing/selftests/rseq/rseq.h index d40d60e7499e..bc68a6127285 100644 --- a/tools/testing/selftests/rseq/rseq.h +++ b/tools/testing/selftests/rseq/rseq.h @@ -79,6 +79,8 @@ extern int __rseq_handled; #include <rseq-mips.h> #elif defined(__s390__) #include <rseq-s390.h> +#elif defined(__riscv) +#include <rseq-riscv.h> #else #error unsupported target #endif
On Mon, 04 Nov 2019 17:58:31 PST (-0800), vincent.chen@sifive.com wrote:
Add RSEQ, restartable sequence, support and related selftest to RISCV. The Kconfig option HAVE_REGS_AND_STACK_ACCESS_API is also required by RSEQ because RSEQ will modify the content of pt_regs.sepc through instruction_pointer_set() during the fixup procedure. In order to select the config HAVE_REGS_AND_STACK_ACCESS_API, the missing APIs for accessing pt_regs are also added in this patch set.
The relevant RSEQ tests in kselftest require the Binutils patch "RISC-V: Fix linker problems with TLS copy relocs" to avoid placing PREINIT_ARRAY and TLS variable of librseq.so at the same address. https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git%3Ba=commit%3Bh=3e7b... A segmental fault will happen if the Binutils misses this patch.
Vincent Chen (3): riscv: add required functions to enable HAVE_REGS_AND_STACK_ACCESS_API riscv: Add support for restartable sequence rseq/selftests: Add support for riscv
arch/riscv/Kconfig | 2 + arch/riscv/include/asm/ptrace.h | 29 +- arch/riscv/kernel/entry.S | 4 + arch/riscv/kernel/ptrace.c | 99 +++++ arch/riscv/kernel/signal.c | 3 + tools/testing/selftests/rseq/param_test.c | 23 ++ tools/testing/selftests/rseq/rseq-riscv.h | 622 ++++++++++++++++++++++++++++++ tools/testing/selftests/rseq/rseq.h | 2 + 8 files changed, 783 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/rseq/rseq-riscv.h
This, with Paul's updated patch 1, isn't building on my end:
In file included from <command-line>: arch/riscv/kernel/ptrace.c:137:18: error: ‘struct pt_regs’ has no member named ‘sepc’; did you mean ‘epc’? REG_OFFSET_NAME(sepc), ^~~~ ././include/linux/compiler_types.h:129:57: note: in definition of macro ‘__compiler_offsetof’ #define __compiler_offsetof(a, b) __builtin_offsetof(a, b) ^ arch/riscv/kernel/ptrace.c:133:51: note: in expansion of macro ‘offsetof’ #define REG_OFFSET_NAME(r) {.name = #r, .offset = offsetof(struct pt_regs, r)} ^~~~~~~~ arch/riscv/kernel/ptrace.c:137:2: note: in expansion of macro ‘REG_OFFSET_NAME’ REG_OFFSET_NAME(sepc), ^~~~~~~~~~~~~~~ arch/riscv/kernel/ptrace.c:169:18: error: ‘struct pt_regs’ has no member named ‘sstatus’; did you mean ‘status’? REG_OFFSET_NAME(sstatus), ^~~~~~~ ././include/linux/compiler_types.h:129:57: note: in definition of macro ‘__compiler_offsetof’ #define __compiler_offsetof(a, b) __builtin_offsetof(a, b) ^ arch/riscv/kernel/ptrace.c:133:51: note: in expansion of macro ‘offsetof’ #define REG_OFFSET_NAME(r) {.name = #r, .offset = offsetof(struct pt_regs, r)} ^~~~~~~~ arch/riscv/kernel/ptrace.c:169:2: note: in expansion of macro ‘REG_OFFSET_NAME’ REG_OFFSET_NAME(sstatus), ^~~~~~~~~~~~~~~ arch/riscv/kernel/ptrace.c:170:18: error: ‘struct pt_regs’ has no member named ‘sbadaddr’; did you mean ‘badaddr’? REG_OFFSET_NAME(sbadaddr), ^~~~~~~~ ././include/linux/compiler_types.h:129:57: note: in definition of macro ‘__compiler_offsetof’ #define __compiler_offsetof(a, b) __builtin_offsetof(a, b) ^ arch/riscv/kernel/ptrace.c:133:51: note: in expansion of macro ‘offsetof’ #define REG_OFFSET_NAME(r) {.name = #r, .offset = offsetof(struct pt_regs, r)} ^~~~~~~~ arch/riscv/kernel/ptrace.c:170:2: note: in expansion of macro ‘REG_OFFSET_NAME’ REG_OFFSET_NAME(sbadaddr), ^~~~~~~~~~~~~~~ arch/riscv/kernel/ptrace.c:171:18: error: ‘struct pt_regs’ has no member named ‘scause’; did you mean ‘cause’? REG_OFFSET_NAME(scause), ^~~~~~ ././include/linux/compiler_types.h:129:57: note: in definition of macro ‘__compiler_offsetof’ #define __compiler_offsetof(a, b) __builtin_offsetof(a, b) ^ arch/riscv/kernel/ptrace.c:133:51: note: in expansion of macro ‘offsetof’ #define REG_OFFSET_NAME(r) {.name = #r, .offset = offsetof(struct pt_regs, r)} ^~~~~~~~ arch/riscv/kernel/ptrace.c:171:2: note: in expansion of macro ‘REG_OFFSET_NAME’ REG_OFFSET_NAME(scause),
On Tue, Jan 14, 2020 at 2:47 AM Palmer Dabbelt palmerdabbelt@google.com wrote:
On Mon, 04 Nov 2019 17:58:31 PST (-0800), vincent.chen@sifive.com wrote:
Add RSEQ, restartable sequence, support and related selftest to RISCV. The Kconfig option HAVE_REGS_AND_STACK_ACCESS_API is also required by RSEQ because RSEQ will modify the content of pt_regs.sepc through instruction_pointer_set() during the fixup procedure. In order to select the config HAVE_REGS_AND_STACK_ACCESS_API, the missing APIs for accessing pt_regs are also added in this patch set.
The relevant RSEQ tests in kselftest require the Binutils patch "RISC-V: Fix linker problems with TLS copy relocs" to avoid placing PREINIT_ARRAY and TLS variable of librseq.so at the same address. https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git%3Ba=commit%3Bh=3e7b... A segmental fault will happen if the Binutils misses this patch.
Vincent Chen (3): riscv: add required functions to enable HAVE_REGS_AND_STACK_ACCESS_API riscv: Add support for restartable sequence rseq/selftests: Add support for riscv
arch/riscv/Kconfig | 2 + arch/riscv/include/asm/ptrace.h | 29 +- arch/riscv/kernel/entry.S | 4 + arch/riscv/kernel/ptrace.c | 99 +++++ arch/riscv/kernel/signal.c | 3 + tools/testing/selftests/rseq/param_test.c | 23 ++ tools/testing/selftests/rseq/rseq-riscv.h | 622 ++++++++++++++++++++++++++++++ tools/testing/selftests/rseq/rseq.h | 2 + 8 files changed, 783 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/rseq/rseq-riscv.h
This, with Paul's updated patch 1, isn't building on my end:
In file included from <command-line>: arch/riscv/kernel/ptrace.c:137:18: error: ‘struct pt_regs’ has no member named ‘sepc’; did you mean ‘epc’? REG_OFFSET_NAME(sepc), ^~~~ ././include/linux/compiler_types.h:129:57: note: in definition of macro ‘__compiler_offsetof’ #define __compiler_offsetof(a, b) __builtin_offsetof(a, b) ^ arch/riscv/kernel/ptrace.c:133:51: note: in expansion of macro ‘offsetof’ #define REG_OFFSET_NAME(r) {.name = #r, .offset = offsetof(struct pt_regs, r)} ^~~~~~~~ arch/riscv/kernel/ptrace.c:137:2: note: in expansion of macro ‘REG_OFFSET_NAME’ REG_OFFSET_NAME(sepc), ^~~~~~~~~~~~~~~ arch/riscv/kernel/ptrace.c:169:18: error: ‘struct pt_regs’ has no member named ‘sstatus’; did you mean ‘status’? REG_OFFSET_NAME(sstatus), ^~~~~~~ ././include/linux/compiler_types.h:129:57: note: in definition of macro ‘__compiler_offsetof’ #define __compiler_offsetof(a, b) __builtin_offsetof(a, b) ^ arch/riscv/kernel/ptrace.c:133:51: note: in expansion of macro ‘offsetof’ #define REG_OFFSET_NAME(r) {.name = #r, .offset = offsetof(struct pt_regs, r)} ^~~~~~~~ arch/riscv/kernel/ptrace.c:169:2: note: in expansion of macro ‘REG_OFFSET_NAME’ REG_OFFSET_NAME(sstatus), ^~~~~~~~~~~~~~~ arch/riscv/kernel/ptrace.c:170:18: error: ‘struct pt_regs’ has no member named ‘sbadaddr’; did you mean ‘badaddr’? REG_OFFSET_NAME(sbadaddr), ^~~~~~~~ ././include/linux/compiler_types.h:129:57: note: in definition of macro ‘__compiler_offsetof’ #define __compiler_offsetof(a, b) __builtin_offsetof(a, b) ^ arch/riscv/kernel/ptrace.c:133:51: note: in expansion of macro ‘offsetof’ #define REG_OFFSET_NAME(r) {.name = #r, .offset = offsetof(struct pt_regs, r)} ^~~~~~~~ arch/riscv/kernel/ptrace.c:170:2: note: in expansion of macro ‘REG_OFFSET_NAME’ REG_OFFSET_NAME(sbadaddr), ^~~~~~~~~~~~~~~ arch/riscv/kernel/ptrace.c:171:18: error: ‘struct pt_regs’ has no member named ‘scause’; did you mean ‘cause’? REG_OFFSET_NAME(scause), ^~~~~~ ././include/linux/compiler_types.h:129:57: note: in definition of macro ‘__compiler_offsetof’ #define __compiler_offsetof(a, b) __builtin_offsetof(a, b) ^ arch/riscv/kernel/ptrace.c:133:51: note: in expansion of macro ‘offsetof’ #define REG_OFFSET_NAME(r) {.name = #r, .offset = offsetof(struct pt_regs, r)} ^~~~~~~~ arch/riscv/kernel/ptrace.c:171:2: note: in expansion of macro ‘REG_OFFSET_NAME’ REG_OFFSET_NAME(scause),
Sorry, I really missed this email. I will fix these errors and resend this patch set. Thank you
linux-kselftest-mirror@lists.linaro.org
-
Palmer Dabbelt -
Paul Walmsley -
Vincent Chen