[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[PATCH v4 20/25] linux-user/riscv: Implement setup_sigtramp
From: |
Richard Henderson |
Subject: |
[PATCH v4 20/25] linux-user/riscv: Implement setup_sigtramp |
Date: |
Mon, 27 Sep 2021 22:00:34 -0400 |
Create and record the rt signal trampoline.
This fixes a bug wrt libgcc fallback unwinding. It expects
the stack pointer to point to the siginfo_t, whereas we had
inexplicably placed our private signal trampoline at the start
of the signal frame instead of the end. Now moot because we
have removed it from the stack frame entirely.
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
linux-user/riscv/target_signal.h | 2 ++
linux-user/riscv/signal.c | 22 +++++++++++++---------
2 files changed, 15 insertions(+), 9 deletions(-)
diff --git a/linux-user/riscv/target_signal.h b/linux-user/riscv/target_signal.h
index f113ba9a55..3e36fddc9d 100644
--- a/linux-user/riscv/target_signal.h
+++ b/linux-user/riscv/target_signal.h
@@ -15,4 +15,6 @@ typedef struct target_sigaltstack {
#include "../generic/signal.h"
+#define TARGET_ARCH_HAS_SIGTRAMP_PAGE 1
+
#endif /* RISCV_TARGET_SIGNAL_H */
diff --git a/linux-user/riscv/signal.c b/linux-user/riscv/signal.c
index f7f33bc90a..a0f9542ce3 100644
--- a/linux-user/riscv/signal.c
+++ b/linux-user/riscv/signal.c
@@ -47,7 +47,6 @@ struct target_ucontext {
};
struct target_rt_sigframe {
- uint32_t tramp[2]; /* not in kernel, which uses VDSO instead */
struct target_siginfo info;
struct target_ucontext uc;
};
@@ -105,12 +104,6 @@ static void setup_ucontext(struct target_ucontext *uc,
setup_sigcontext(&uc->uc_mcontext, env);
}
-static inline void install_sigtramp(uint32_t *tramp)
-{
- __put_user(0x08b00893, tramp + 0); /* li a7, 139 = __NR_rt_sigreturn */
- __put_user(0x00000073, tramp + 1); /* ecall */
-}
-
void setup_rt_frame(int sig, struct target_sigaction *ka,
target_siginfo_t *info,
target_sigset_t *set, CPURISCVState *env)
@@ -127,14 +120,13 @@ void setup_rt_frame(int sig, struct target_sigaction *ka,
setup_ucontext(&frame->uc, env, set);
tswap_siginfo(&frame->info, info);
- install_sigtramp(frame->tramp);
env->pc = ka->_sa_handler;
env->gpr[xSP] = frame_addr;
env->gpr[xA0] = sig;
env->gpr[xA1] = frame_addr + offsetof(struct target_rt_sigframe, info);
env->gpr[xA2] = frame_addr + offsetof(struct target_rt_sigframe, uc);
- env->gpr[xRA] = frame_addr + offsetof(struct target_rt_sigframe, tramp);
+ env->gpr[xRA] = default_rt_sigreturn;
return;
@@ -203,3 +195,15 @@ badframe:
force_sig(TARGET_SIGSEGV);
return 0;
}
+
+void setup_sigtramp(abi_ulong sigtramp_page)
+{
+ uint32_t *tramp = lock_user(VERIFY_WRITE, sigtramp_page, 8, 0);
+ assert(tramp != NULL);
+
+ __put_user(0x08b00893, tramp + 0); /* li a7, 139 = __NR_rt_sigreturn */
+ __put_user(0x00000073, tramp + 1); /* ecall */
+
+ default_rt_sigreturn = sigtramp_page;
+ unlock_user(tramp, sigtramp_page, 8);
+}
--
2.25.1
- [PATCH v4 12/25] linux-user/m68k: Implement setup_sigtramp, (continued)
- [PATCH v4 12/25] linux-user/m68k: Implement setup_sigtramp, Richard Henderson, 2021/09/27
- [PATCH v4 16/25] linux-user/nios2: Document non-use of setup_sigtramp, Richard Henderson, 2021/09/27
- [PATCH v4 18/25] linux-user/ppc: Simplify encode_trampoline, Richard Henderson, 2021/09/27
- [PATCH v4 07/25] linux-user/cris: Implement setup_sigtramp, Richard Henderson, 2021/09/27
- [PATCH v4 09/25] linux-user/hppa: Document non-use of setup_sigtramp, Richard Henderson, 2021/09/27
- [PATCH v4 13/25] linux-user/microblaze: Implement setup_sigtramp, Richard Henderson, 2021/09/27
- [PATCH v4 19/25] linux-user/ppc: Implement setup_sigtramp, Richard Henderson, 2021/09/27
- [PATCH v4 22/25] linux-user/sh4: Implement setup_sigtramp, Richard Henderson, 2021/09/27
- [PATCH v4 23/25] linux-user/sparc: Implement setup_sigtramp, Richard Henderson, 2021/09/27
- [PATCH v4 15/25] linux-user/mips: Implement setup_sigtramp, Richard Henderson, 2021/09/27
- [PATCH v4 20/25] linux-user/riscv: Implement setup_sigtramp,
Richard Henderson <=
- [PATCH v4 25/25] linux-user: Remove default for TARGET_ARCH_HAS_SIGTRAMP_PAGE, Richard Henderson, 2021/09/27
- [PATCH v4 04/25] linux-user/arm: Drop "_v2" from symbols in signal.c, Richard Henderson, 2021/09/27
- [PATCH v4 24/25] linux-user/xtensa: Implement setup_sigtramp, Richard Henderson, 2021/09/27
- [PATCH v4 08/25] linux-user/hexagon: Implement setup_sigtramp, Richard Henderson, 2021/09/27
- [PATCH v4 17/25] linux-user/openrisc: Implement setup_sigtramp, Richard Henderson, 2021/09/27
- [PATCH v4 21/25] linux-user/s390x: Implement setup_sigtramp, Richard Henderson, 2021/09/27