From: Warner Losh <imp@bsdimp.com>
To: qemu-devel@nongnu.org
Cc: Richard Henderson <richard.henderson@linaro.org>,
Philippe Mathieu-Daude <f4bug@amsat.org>,
Laurent Vivier <laurent@vivier.eu>,
Konrad Witaszczyk <def@freebsd.org>, Warner Losh <imp@bsdimp.com>
Subject: [RFC v3 2/5] linux-user/signal.c: Create a common rewind_if_in_safe_syscall
Date: Fri, 12 Nov 2021 21:56:00 -0700 [thread overview]
Message-ID: <20211113045603.60391-3-imp@bsdimp.com> (raw)
In-Reply-To: <20211113045603.60391-1-imp@bsdimp.com>
All instances of rewind_if_in_safe_syscall are the same, differing only
in how the instruction point is fetched from the ucontext and the size
of the registers. Use host_signal_pc and new host_signal_set_pc
interfaces to fetch the pointer to the PC and adjust if needed. Delete
all the old copies of rewind_if_in_safe_syscall.
Signed-off-by: Warner Losh <imp@bsdimp.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
---
linux-user/host/aarch64/hostdep.h | 20 --------------------
linux-user/host/arm/hostdep.h | 20 --------------------
linux-user/host/i386/hostdep.h | 20 --------------------
linux-user/host/ppc64/hostdep.h | 20 --------------------
linux-user/host/riscv/hostdep.h | 20 --------------------
linux-user/host/s390x/hostdep.h | 20 --------------------
linux-user/host/x86_64/hostdep.h | 20 --------------------
linux-user/safe-syscall.h | 3 +++
linux-user/signal.c | 14 +++++++++++++-
9 files changed, 16 insertions(+), 141 deletions(-)
diff --git a/linux-user/host/aarch64/hostdep.h b/linux-user/host/aarch64/hostdep.h
index a8d41a21ad..39299d798a 100644
--- a/linux-user/host/aarch64/hostdep.h
+++ b/linux-user/host/aarch64/hostdep.h
@@ -15,24 +15,4 @@
/* We have a safe-syscall.inc.S */
#define HAVE_SAFE_SYSCALL
-#ifndef __ASSEMBLER__
-
-/* These are defined by the safe-syscall.inc.S file */
-extern char safe_syscall_start[];
-extern char safe_syscall_end[];
-
-/* Adjust the signal context to rewind out of safe-syscall if we're in it */
-static inline void rewind_if_in_safe_syscall(void *puc)
-{
- ucontext_t *uc = puc;
- __u64 *pcreg = &uc->uc_mcontext.pc;
-
- if (*pcreg > (uintptr_t)safe_syscall_start
- && *pcreg < (uintptr_t)safe_syscall_end) {
- *pcreg = (uintptr_t)safe_syscall_start;
- }
-}
-
-#endif /* __ASSEMBLER__ */
-
#endif
diff --git a/linux-user/host/arm/hostdep.h b/linux-user/host/arm/hostdep.h
index 9276fe6ceb..86b137875a 100644
--- a/linux-user/host/arm/hostdep.h
+++ b/linux-user/host/arm/hostdep.h
@@ -15,24 +15,4 @@
/* We have a safe-syscall.inc.S */
#define HAVE_SAFE_SYSCALL
-#ifndef __ASSEMBLER__
-
-/* These are defined by the safe-syscall.inc.S file */
-extern char safe_syscall_start[];
-extern char safe_syscall_end[];
-
-/* Adjust the signal context to rewind out of safe-syscall if we're in it */
-static inline void rewind_if_in_safe_syscall(void *puc)
-{
- ucontext_t *uc = puc;
- unsigned long *pcreg = &uc->uc_mcontext.arm_pc;
-
- if (*pcreg > (uintptr_t)safe_syscall_start
- && *pcreg < (uintptr_t)safe_syscall_end) {
- *pcreg = (uintptr_t)safe_syscall_start;
- }
-}
-
-#endif /* __ASSEMBLER__ */
-
#endif
diff --git a/linux-user/host/i386/hostdep.h b/linux-user/host/i386/hostdep.h
index 073be74d87..ce7136501f 100644
--- a/linux-user/host/i386/hostdep.h
+++ b/linux-user/host/i386/hostdep.h
@@ -15,24 +15,4 @@
/* We have a safe-syscall.inc.S */
#define HAVE_SAFE_SYSCALL
-#ifndef __ASSEMBLER__
-
-/* These are defined by the safe-syscall.inc.S file */
-extern char safe_syscall_start[];
-extern char safe_syscall_end[];
-
-/* Adjust the signal context to rewind out of safe-syscall if we're in it */
-static inline void rewind_if_in_safe_syscall(void *puc)
-{
- ucontext_t *uc = puc;
- greg_t *pcreg = &uc->uc_mcontext.gregs[REG_EIP];
-
- if (*pcreg > (uintptr_t)safe_syscall_start
- && *pcreg < (uintptr_t)safe_syscall_end) {
- *pcreg = (uintptr_t)safe_syscall_start;
- }
-}
-
-#endif /* __ASSEMBLER__ */
-
#endif
diff --git a/linux-user/host/ppc64/hostdep.h b/linux-user/host/ppc64/hostdep.h
index 98979ad917..0c290dd904 100644
--- a/linux-user/host/ppc64/hostdep.h
+++ b/linux-user/host/ppc64/hostdep.h
@@ -15,24 +15,4 @@
/* We have a safe-syscall.inc.S */
#define HAVE_SAFE_SYSCALL
-#ifndef __ASSEMBLER__
-
-/* These are defined by the safe-syscall.inc.S file */
-extern char safe_syscall_start[];
-extern char safe_syscall_end[];
-
-/* Adjust the signal context to rewind out of safe-syscall if we're in it */
-static inline void rewind_if_in_safe_syscall(void *puc)
-{
- ucontext_t *uc = puc;
- unsigned long *pcreg = &uc->uc_mcontext.gp_regs[PT_NIP];
-
- if (*pcreg > (uintptr_t)safe_syscall_start
- && *pcreg < (uintptr_t)safe_syscall_end) {
- *pcreg = (uintptr_t)safe_syscall_start;
- }
-}
-
-#endif /* __ASSEMBLER__ */
-
#endif
diff --git a/linux-user/host/riscv/hostdep.h b/linux-user/host/riscv/hostdep.h
index 2ba07456ae..7f67c22868 100644
--- a/linux-user/host/riscv/hostdep.h
+++ b/linux-user/host/riscv/hostdep.h
@@ -11,24 +11,4 @@
/* We have a safe-syscall.inc.S */
#define HAVE_SAFE_SYSCALL
-#ifndef __ASSEMBLER__
-
-/* These are defined by the safe-syscall.inc.S file */
-extern char safe_syscall_start[];
-extern char safe_syscall_end[];
-
-/* Adjust the signal context to rewind out of safe-syscall if we're in it */
-static inline void rewind_if_in_safe_syscall(void *puc)
-{
- ucontext_t *uc = puc;
- unsigned long *pcreg = &uc->uc_mcontext.__gregs[REG_PC];
-
- if (*pcreg > (uintptr_t)safe_syscall_start
- && *pcreg < (uintptr_t)safe_syscall_end) {
- *pcreg = (uintptr_t)safe_syscall_start;
- }
-}
-
-#endif /* __ASSEMBLER__ */
-
#endif
diff --git a/linux-user/host/s390x/hostdep.h b/linux-user/host/s390x/hostdep.h
index 4f0171f36f..d801145854 100644
--- a/linux-user/host/s390x/hostdep.h
+++ b/linux-user/host/s390x/hostdep.h
@@ -15,24 +15,4 @@
/* We have a safe-syscall.inc.S */
#define HAVE_SAFE_SYSCALL
-#ifndef __ASSEMBLER__
-
-/* These are defined by the safe-syscall.inc.S file */
-extern char safe_syscall_start[];
-extern char safe_syscall_end[];
-
-/* Adjust the signal context to rewind out of safe-syscall if we're in it */
-static inline void rewind_if_in_safe_syscall(void *puc)
-{
- ucontext_t *uc = puc;
- unsigned long *pcreg = &uc->uc_mcontext.psw.addr;
-
- if (*pcreg > (uintptr_t)safe_syscall_start
- && *pcreg < (uintptr_t)safe_syscall_end) {
- *pcreg = (uintptr_t)safe_syscall_start;
- }
-}
-
-#endif /* __ASSEMBLER__ */
-
#endif
diff --git a/linux-user/host/x86_64/hostdep.h b/linux-user/host/x86_64/hostdep.h
index a4fefb5114..9c62bd26bd 100644
--- a/linux-user/host/x86_64/hostdep.h
+++ b/linux-user/host/x86_64/hostdep.h
@@ -15,24 +15,4 @@
/* We have a safe-syscall.inc.S */
#define HAVE_SAFE_SYSCALL
-#ifndef __ASSEMBLER__
-
-/* These are defined by the safe-syscall.inc.S file */
-extern char safe_syscall_start[];
-extern char safe_syscall_end[];
-
-/* Adjust the signal context to rewind out of safe-syscall if we're in it */
-static inline void rewind_if_in_safe_syscall(void *puc)
-{
- ucontext_t *uc = puc;
- greg_t *pcreg = &uc->uc_mcontext.gregs[REG_RIP];
-
- if (*pcreg > (uintptr_t)safe_syscall_start
- && *pcreg < (uintptr_t)safe_syscall_end) {
- *pcreg = (uintptr_t)safe_syscall_start;
- }
-}
-
-#endif /* __ASSEMBLER__ */
-
#endif
diff --git a/linux-user/safe-syscall.h b/linux-user/safe-syscall.h
index 6bc0390262..aaa9ffc0e2 100644
--- a/linux-user/safe-syscall.h
+++ b/linux-user/safe-syscall.h
@@ -127,6 +127,9 @@
#ifdef HAVE_SAFE_SYSCALL
/* The core part of this function is implemented in assembly */
extern long safe_syscall_base(int *pending, long number, ...);
+/* These are defined by the safe-syscall.inc.S file */
+extern char safe_syscall_start[];
+extern char safe_syscall_end[];
#define safe_syscall(...) \
({ \
diff --git a/linux-user/signal.c b/linux-user/signal.c
index 81c45bfce9..ee038c2399 100644
--- a/linux-user/signal.c
+++ b/linux-user/signal.c
@@ -793,7 +793,19 @@ int queue_signal(CPUArchState *env, int sig, int si_type,
return 1; /* indicates that the signal was queued */
}
-#ifndef HAVE_SAFE_SYSCALL
+#ifdef HAVE_SAFE_SYSCALL
+/* Adjust the signal context to rewind out of safe-syscall if we're in it */
+static inline void rewind_if_in_safe_syscall(void *puc)
+{
+ ucontext_t *uc = (ucontext_t *)puc;
+ uintptr_t pcreg = host_signal_pc(uc);
+
+ if (pcreg > (uintptr_t)safe_syscall_start
+ && pcreg < (uintptr_t)safe_syscall_end) {
+ host_signal_set_pc(uc, (uintptr_t)safe_syscall_start);
+ }
+}
+#else
static inline void rewind_if_in_safe_syscall(void *puc)
{
/* Default version: never rewind */
--
2.33.0
next prev parent reply other threads:[~2021-11-13 5:00 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-11-13 4:55 [RFC v3 0/5] linux-user: simplify safe signal handling Warner Losh
2021-11-13 4:55 ` [RFC v3 1/5] linux-user: Add host_signal_set_pc to set pc in mcontext Warner Losh
2021-11-13 4:56 ` Warner Losh [this message]
2021-11-13 4:56 ` [RFC v3 3/5] linux-user/safe-syscall.inc.S: Move to common-user Warner Losh
2021-11-13 4:56 ` [RFC v3 4/5] common-user: Adjust system call return on FreeBSD Warner Losh
2021-11-14 9:20 ` Richard Henderson
2021-11-13 4:56 ` [RFC v3 5/5] *-user: move safe-syscall.* to common-user Warner Losh
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