[PATCH for-6.2 0/2] linux-user: Create a common rewind_if_in_safe_syscall

[PATCH for-6.2 0/2] linux-user: Create a common rewind_if_in_safe_syscall

[Richard Henderson]

This is a re-packaging of two of Warner's patches that
fix a build issue on aarch64 using musl:

https://lore.kernel.org/qemu-devel/20211108194230.1836262-1-raj.khem@gmail.com/


r~


Warner Losh (2):
  linux-user: Add host_signal_set_pc to set pc in mcontext
  linux-user/signal.c: Create a common rewind_if_in_safe_syscall

 linux-user/host/aarch64/host-signal.h |  5 +++++
 linux-user/host/aarch64/hostdep.h     | 20 --------------------
 linux-user/host/alpha/host-signal.h   |  5 +++++
 linux-user/host/arm/host-signal.h     |  5 +++++
 linux-user/host/arm/hostdep.h         | 20 --------------------
 linux-user/host/i386/host-signal.h    |  5 +++++
 linux-user/host/i386/hostdep.h        | 20 --------------------
 linux-user/host/mips/host-signal.h    |  5 +++++
 linux-user/host/ppc/host-signal.h     |  5 +++++
 linux-user/host/ppc64/hostdep.h       | 20 --------------------
 linux-user/host/riscv/host-signal.h   |  5 +++++
 linux-user/host/riscv/hostdep.h       | 20 --------------------
 linux-user/host/s390/host-signal.h    |  5 +++++
 linux-user/host/s390x/hostdep.h       | 20 --------------------
 linux-user/host/sparc/host-signal.h   |  9 +++++++++
 linux-user/host/x86_64/host-signal.h  |  5 +++++
 linux-user/host/x86_64/hostdep.h      | 20 --------------------
 linux-user/safe-syscall.h             |  3 +++
 linux-user/signal.c                   | 15 ++++++++++++---
 19 files changed, 69 insertions(+), 143 deletions(-)

-- 
2.25.1

[PATCH for-6.2 1/2] linux-user: Add host_signal_set_pc to set pc in mcontext

[Richard Henderson]

From: Warner Losh <imp@bsdimp.com>

Add a new function host_signal_set_pc to set the next pc in an
mcontext. The caller should ensure this is a valid PC for execution.

Signed-off-by: Warner Losh <imp@bsdimp.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211113045603.60391-2-imp@bsdimp.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 linux-user/host/aarch64/host-signal.h | 5 +++++
 linux-user/host/alpha/host-signal.h   | 5 +++++
 linux-user/host/arm/host-signal.h     | 5 +++++
 linux-user/host/i386/host-signal.h    | 5 +++++
 linux-user/host/mips/host-signal.h    | 5 +++++
 linux-user/host/ppc/host-signal.h     | 5 +++++
 linux-user/host/riscv/host-signal.h   | 5 +++++
 linux-user/host/s390/host-signal.h    | 5 +++++
 linux-user/host/sparc/host-signal.h   | 9 +++++++++
 linux-user/host/x86_64/host-signal.h  | 5 +++++
 10 files changed, 54 insertions(+)

diff --git a/linux-user/host/aarch64/host-signal.h b/linux-user/host/aarch64/host-signal.h
index 0c0b08383a..9770b36dc1 100644
--- a/linux-user/host/aarch64/host-signal.h
+++ b/linux-user/host/aarch64/host-signal.h
@@ -35,6 +35,11 @@ static inline uintptr_t host_signal_pc(ucontext_t *uc)
     return uc->uc_mcontext.pc;
 }
 
+static inline void host_signal_set_pc(ucontext_t *uc, uintptr_t pc)
+{
+    uc->uc_mcontext.pc = pc;
+}
+
 static inline bool host_signal_write(siginfo_t *info, ucontext_t *uc)
 {
     struct _aarch64_ctx *hdr;
diff --git a/linux-user/host/alpha/host-signal.h b/linux-user/host/alpha/host-signal.h
index e080be412f..f4c942948a 100644
--- a/linux-user/host/alpha/host-signal.h
+++ b/linux-user/host/alpha/host-signal.h
@@ -16,6 +16,11 @@ static inline uintptr_t host_signal_pc(ucontext_t *uc)
     return uc->uc_mcontext.sc_pc;
 }
 
+static inline void host_signal_set_pc(ucontext_t *uc, uintptr_t pc)
+{
+    uc->uc_mcontext.sc_pc = pc;
+}
+
 static inline bool host_signal_write(siginfo_t *info, ucontext_t *uc)
 {
     uint32_t *pc = (uint32_t *)host_signal_pc(uc);
diff --git a/linux-user/host/arm/host-signal.h b/linux-user/host/arm/host-signal.h
index efb165c0c5..6c095773c0 100644
--- a/linux-user/host/arm/host-signal.h
+++ b/linux-user/host/arm/host-signal.h
@@ -16,6 +16,11 @@ static inline uintptr_t host_signal_pc(ucontext_t *uc)
     return uc->uc_mcontext.arm_pc;
 }
 
+static inline void host_signal_set_pc(ucontext_t *uc, uintptr_t pc)
+{
+    uc->uc_mcontext.arm_pc = pc;
+}
+
 static inline bool host_signal_write(siginfo_t *info, ucontext_t *uc)
 {
     /*
diff --git a/linux-user/host/i386/host-signal.h b/linux-user/host/i386/host-signal.h
index 4c8eef99ce..abe1ece5c9 100644
--- a/linux-user/host/i386/host-signal.h
+++ b/linux-user/host/i386/host-signal.h
@@ -16,6 +16,11 @@ static inline uintptr_t host_signal_pc(ucontext_t *uc)
     return uc->uc_mcontext.gregs[REG_EIP];
 }
 
+static inline void host_signal_set_pc(ucontext_t *uc, uintptr_t pc)
+{
+    uc->uc_mcontext.gregs[REG_EIP] = pc;
+}
+
 static inline bool host_signal_write(siginfo_t *info, ucontext_t *uc)
 {
     return uc->uc_mcontext.gregs[REG_TRAPNO] == 0xe
diff --git a/linux-user/host/mips/host-signal.h b/linux-user/host/mips/host-signal.h
index ef341f7c20..c666ed8c3f 100644
--- a/linux-user/host/mips/host-signal.h
+++ b/linux-user/host/mips/host-signal.h
@@ -16,6 +16,11 @@ static inline uintptr_t host_signal_pc(ucontext_t *uc)
     return uc->uc_mcontext.pc;
 }
 
+static inline void host_signal_set_pc(ucontext_t *uc, uintptr_t pc)
+{
+    uc->uc_mcontext.pc = pc;
+}
+
 #if defined(__misp16) || defined(__mips_micromips)
 #error "Unsupported encoding"
 #endif
diff --git a/linux-user/host/ppc/host-signal.h b/linux-user/host/ppc/host-signal.h
index a491c413dc..1d8e658ff7 100644
--- a/linux-user/host/ppc/host-signal.h
+++ b/linux-user/host/ppc/host-signal.h
@@ -16,6 +16,11 @@ static inline uintptr_t host_signal_pc(ucontext_t *uc)
     return uc->uc_mcontext.regs->nip;
 }
 
+static inline void host_signal_set_pc(ucontext_t *uc, uintptr_t pc)
+{
+    uc->uc_mcontext.regs->nip = pc;
+}
+
 static inline bool host_signal_write(siginfo_t *info, ucontext_t *uc)
 {
     return uc->uc_mcontext.regs->trap != 0x400
diff --git a/linux-user/host/riscv/host-signal.h b/linux-user/host/riscv/host-signal.h
index 3b168cb58b..a4f170efb0 100644
--- a/linux-user/host/riscv/host-signal.h
+++ b/linux-user/host/riscv/host-signal.h
@@ -16,6 +16,11 @@ static inline uintptr_t host_signal_pc(ucontext_t *uc)
     return uc->uc_mcontext.__gregs[REG_PC];
 }
 
+static inline void host_signal_set_pc(ucontext_t *uc, uintptr_t pc)
+{
+    uc->uc_mcontext.__gregs[REG_PC] = pc;
+}
+
 static inline bool host_signal_write(siginfo_t *info, ucontext_t *uc)
 {
     /*
diff --git a/linux-user/host/s390/host-signal.h b/linux-user/host/s390/host-signal.h
index 26990e4893..a524f2ab00 100644
--- a/linux-user/host/s390/host-signal.h
+++ b/linux-user/host/s390/host-signal.h
@@ -16,6 +16,11 @@ static inline uintptr_t host_signal_pc(ucontext_t *uc)
     return uc->uc_mcontext.psw.addr;
 }
 
+static inline void host_signal_set_pc(ucontext_t *uc, uintptr_t pc)
+{
+    uc->uc_mcontext.psw.addr = pc;
+}
+
 static inline bool host_signal_write(siginfo_t *info, ucontext_t *uc)
 {
     uint16_t *pinsn = (uint16_t *)host_signal_pc(uc);
diff --git a/linux-user/host/sparc/host-signal.h b/linux-user/host/sparc/host-signal.h
index 5e71d33f8e..7342936071 100644
--- a/linux-user/host/sparc/host-signal.h
+++ b/linux-user/host/sparc/host-signal.h
@@ -20,6 +20,15 @@ static inline uintptr_t host_signal_pc(ucontext_t *uc)
 #endif
 }
 
+static inline void host_signal_set_pc(ucontext_t *uc, uintptr_t pc)
+{
+#ifdef __arch64__
+    uc->uc_mcontext.mc_gregs[MC_PC] = pc;
+#else
+    uc->uc_mcontext.gregs[REG_PC] = pc;
+#endif
+}
+
 static inline bool host_signal_write(siginfo_t *info, ucontext_t *uc)
 {
     uint32_t insn = *(uint32_t *)host_signal_pc(uc);
diff --git a/linux-user/host/x86_64/host-signal.h b/linux-user/host/x86_64/host-signal.h
index 883d2fcf65..c71d597eb2 100644
--- a/linux-user/host/x86_64/host-signal.h
+++ b/linux-user/host/x86_64/host-signal.h
@@ -15,6 +15,11 @@ static inline uintptr_t host_signal_pc(ucontext_t *uc)
     return uc->uc_mcontext.gregs[REG_RIP];
 }
 
+static inline void host_signal_set_pc(ucontext_t *uc, uintptr_t pc)
+{
+    uc->uc_mcontext.gregs[REG_RIP] = pc;
+}
+
 static inline bool host_signal_write(siginfo_t *info, ucontext_t *uc)
 {
     return uc->uc_mcontext.gregs[REG_TRAPNO] == 0xe
-- 
2.25.1

[PATCH for-6.2 2/2] linux-user/signal.c: Create a common rewind_if_in_safe_syscall

[Richard Henderson]

From: Warner Losh <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>
Message-Id: <20211113045603.60391-3-imp@bsdimp.com>
[rth: include safe-syscall.h, simplify ifdefs]
Signed-off-by: Richard Henderson <richard.henderson@linaro.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               | 15 ++++++++++++---
 9 files changed, 15 insertions(+), 143 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..6d5e5b698c 100644
--- a/linux-user/signal.c
+++ b/linux-user/signal.c
@@ -31,6 +31,7 @@
 #include "trace.h"
 #include "signal-common.h"
 #include "host-signal.h"
+#include "safe-syscall.h"
 
 static struct target_sigaction sigact_table[TARGET_NSIG];
 
@@ -793,12 +794,20 @@ int queue_signal(CPUArchState *env, int sig, int si_type,
     return 1; /* indicates that the signal was queued */
 }
 
-#ifndef 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)
 {
-    /* Default version: never rewind */
-}
+#ifdef HAVE_SAFE_SYSCALL
+    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);
+    }
 #endif
+}
 
 static void host_signal_handler(int host_sig, siginfo_t *info, void *puc)
 {
-- 
2.25.1

Re: [PATCH for-6.2 2/2] linux-user/signal.c: Create a common rewind_if_in_safe_syscall

[Warner Losh]

[-- Attachment #1: Type: text/plain, Size: 9938 bytes --]

On Mon, Nov 22, 2021 at 6:12 AM Richard Henderson <
richard.henderson@linaro.org> wrote:

> From: Warner Losh <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>
> Message-Id: <20211113045603.60391-3-imp@bsdimp.com>
> [rth: include safe-syscall.h, simplify ifdefs]
> Signed-off-by: Richard Henderson <richard.henderson@linaro.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               | 15 ++++++++++++---
>  9 files changed, 15 insertions(+), 143 deletions(-)
>

Reviewed-by: Warner Losh <imp@bsdimp.com>

The changes to what I wrote look good.

Warner


> 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..6d5e5b698c 100644
> --- a/linux-user/signal.c
> +++ b/linux-user/signal.c
> @@ -31,6 +31,7 @@
>  #include "trace.h"
>  #include "signal-common.h"
>  #include "host-signal.h"
> +#include "safe-syscall.h"
>
>  static struct target_sigaction sigact_table[TARGET_NSIG];
>
> @@ -793,12 +794,20 @@ int queue_signal(CPUArchState *env, int sig, int
> si_type,
>      return 1; /* indicates that the signal was queued */
>  }
>
> -#ifndef 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)
>  {
> -    /* Default version: never rewind */
> -}
> +#ifdef HAVE_SAFE_SYSCALL
> +    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);
> +    }
>  #endif
> +}
>
>  static void host_signal_handler(int host_sig, siginfo_t *info, void *puc)
>  {
> --
> 2.25.1
>
>

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Re: [PATCH for-6.2 1/2] linux-user: Add host_signal_set_pc to set pc in mcontext

[Warner Losh]

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On Mon, Nov 22, 2021 at 6:12 AM Richard Henderson <
richard.henderson@linaro.org> wrote:

> From: Warner Losh <imp@bsdimp.com>
>
> Add a new function host_signal_set_pc to set the next pc in an
> mcontext. The caller should ensure this is a valid PC for execution.
>
> Signed-off-by: Warner Losh <imp@bsdimp.com>
> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
> Message-Id: <20211113045603.60391-2-imp@bsdimp.com>
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---
>  linux-user/host/aarch64/host-signal.h | 5 +++++
>  linux-user/host/alpha/host-signal.h   | 5 +++++
>  linux-user/host/arm/host-signal.h     | 5 +++++
>  linux-user/host/i386/host-signal.h    | 5 +++++
>  linux-user/host/mips/host-signal.h    | 5 +++++
>  linux-user/host/ppc/host-signal.h     | 5 +++++
>  linux-user/host/riscv/host-signal.h   | 5 +++++
>  linux-user/host/s390/host-signal.h    | 5 +++++
>  linux-user/host/sparc/host-signal.h   | 9 +++++++++
>  linux-user/host/x86_64/host-signal.h  | 5 +++++
>  10 files changed, 54 insertions(+)
>

Reviewed-by: Warner Losh <imp@bsdimp.com>

This looks like what I submitted, and will work with the cleaned up other
half.

Warner


> diff --git a/linux-user/host/aarch64/host-signal.h
> b/linux-user/host/aarch64/host-signal.h
> index 0c0b08383a..9770b36dc1 100644
> --- a/linux-user/host/aarch64/host-signal.h
> +++ b/linux-user/host/aarch64/host-signal.h
> @@ -35,6 +35,11 @@ static inline uintptr_t host_signal_pc(ucontext_t *uc)
>      return uc->uc_mcontext.pc;
>  }
>
> +static inline void host_signal_set_pc(ucontext_t *uc, uintptr_t pc)
> +{
> +    uc->uc_mcontext.pc = pc;
> +}
> +
>  static inline bool host_signal_write(siginfo_t *info, ucontext_t *uc)
>  {
>      struct _aarch64_ctx *hdr;
> diff --git a/linux-user/host/alpha/host-signal.h
> b/linux-user/host/alpha/host-signal.h
> index e080be412f..f4c942948a 100644
> --- a/linux-user/host/alpha/host-signal.h
> +++ b/linux-user/host/alpha/host-signal.h
> @@ -16,6 +16,11 @@ static inline uintptr_t host_signal_pc(ucontext_t *uc)
>      return uc->uc_mcontext.sc_pc;
>  }
>
> +static inline void host_signal_set_pc(ucontext_t *uc, uintptr_t pc)
> +{
> +    uc->uc_mcontext.sc_pc = pc;
> +}
> +
>  static inline bool host_signal_write(siginfo_t *info, ucontext_t *uc)
>  {
>      uint32_t *pc = (uint32_t *)host_signal_pc(uc);
> diff --git a/linux-user/host/arm/host-signal.h
> b/linux-user/host/arm/host-signal.h
> index efb165c0c5..6c095773c0 100644
> --- a/linux-user/host/arm/host-signal.h
> +++ b/linux-user/host/arm/host-signal.h
> @@ -16,6 +16,11 @@ static inline uintptr_t host_signal_pc(ucontext_t *uc)
>      return uc->uc_mcontext.arm_pc;
>  }
>
> +static inline void host_signal_set_pc(ucontext_t *uc, uintptr_t pc)
> +{
> +    uc->uc_mcontext.arm_pc = pc;
> +}
> +
>  static inline bool host_signal_write(siginfo_t *info, ucontext_t *uc)
>  {
>      /*
> diff --git a/linux-user/host/i386/host-signal.h
> b/linux-user/host/i386/host-signal.h
> index 4c8eef99ce..abe1ece5c9 100644
> --- a/linux-user/host/i386/host-signal.h
> +++ b/linux-user/host/i386/host-signal.h
> @@ -16,6 +16,11 @@ static inline uintptr_t host_signal_pc(ucontext_t *uc)
>      return uc->uc_mcontext.gregs[REG_EIP];
>  }
>
> +static inline void host_signal_set_pc(ucontext_t *uc, uintptr_t pc)
> +{
> +    uc->uc_mcontext.gregs[REG_EIP] = pc;
> +}
> +
>  static inline bool host_signal_write(siginfo_t *info, ucontext_t *uc)
>  {
>      return uc->uc_mcontext.gregs[REG_TRAPNO] == 0xe
> diff --git a/linux-user/host/mips/host-signal.h
> b/linux-user/host/mips/host-signal.h
> index ef341f7c20..c666ed8c3f 100644
> --- a/linux-user/host/mips/host-signal.h
> +++ b/linux-user/host/mips/host-signal.h
> @@ -16,6 +16,11 @@ static inline uintptr_t host_signal_pc(ucontext_t *uc)
>      return uc->uc_mcontext.pc;
>  }
>
> +static inline void host_signal_set_pc(ucontext_t *uc, uintptr_t pc)
> +{
> +    uc->uc_mcontext.pc = pc;
> +}
> +
>  #if defined(__misp16) || defined(__mips_micromips)
>  #error "Unsupported encoding"
>  #endif
> diff --git a/linux-user/host/ppc/host-signal.h
> b/linux-user/host/ppc/host-signal.h
> index a491c413dc..1d8e658ff7 100644
> --- a/linux-user/host/ppc/host-signal.h
> +++ b/linux-user/host/ppc/host-signal.h
> @@ -16,6 +16,11 @@ static inline uintptr_t host_signal_pc(ucontext_t *uc)
>      return uc->uc_mcontext.regs->nip;
>  }
>
> +static inline void host_signal_set_pc(ucontext_t *uc, uintptr_t pc)
> +{
> +    uc->uc_mcontext.regs->nip = pc;
> +}
> +
>  static inline bool host_signal_write(siginfo_t *info, ucontext_t *uc)
>  {
>      return uc->uc_mcontext.regs->trap != 0x400
> diff --git a/linux-user/host/riscv/host-signal.h
> b/linux-user/host/riscv/host-signal.h
> index 3b168cb58b..a4f170efb0 100644
> --- a/linux-user/host/riscv/host-signal.h
> +++ b/linux-user/host/riscv/host-signal.h
> @@ -16,6 +16,11 @@ static inline uintptr_t host_signal_pc(ucontext_t *uc)
>      return uc->uc_mcontext.__gregs[REG_PC];
>  }
>
> +static inline void host_signal_set_pc(ucontext_t *uc, uintptr_t pc)
> +{
> +    uc->uc_mcontext.__gregs[REG_PC] = pc;
> +}
> +
>  static inline bool host_signal_write(siginfo_t *info, ucontext_t *uc)
>  {
>      /*
> diff --git a/linux-user/host/s390/host-signal.h
> b/linux-user/host/s390/host-signal.h
> index 26990e4893..a524f2ab00 100644
> --- a/linux-user/host/s390/host-signal.h
> +++ b/linux-user/host/s390/host-signal.h
> @@ -16,6 +16,11 @@ static inline uintptr_t host_signal_pc(ucontext_t *uc)
>      return uc->uc_mcontext.psw.addr;
>  }
>
> +static inline void host_signal_set_pc(ucontext_t *uc, uintptr_t pc)
> +{
> +    uc->uc_mcontext.psw.addr = pc;
> +}
> +
>  static inline bool host_signal_write(siginfo_t *info, ucontext_t *uc)
>  {
>      uint16_t *pinsn = (uint16_t *)host_signal_pc(uc);
> diff --git a/linux-user/host/sparc/host-signal.h
> b/linux-user/host/sparc/host-signal.h
> index 5e71d33f8e..7342936071 100644
> --- a/linux-user/host/sparc/host-signal.h
> +++ b/linux-user/host/sparc/host-signal.h
> @@ -20,6 +20,15 @@ static inline uintptr_t host_signal_pc(ucontext_t *uc)
>  #endif
>  }
>
> +static inline void host_signal_set_pc(ucontext_t *uc, uintptr_t pc)
> +{
> +#ifdef __arch64__
> +    uc->uc_mcontext.mc_gregs[MC_PC] = pc;
> +#else
> +    uc->uc_mcontext.gregs[REG_PC] = pc;
> +#endif
> +}
> +
>  static inline bool host_signal_write(siginfo_t *info, ucontext_t *uc)
>  {
>      uint32_t insn = *(uint32_t *)host_signal_pc(uc);
> diff --git a/linux-user/host/x86_64/host-signal.h
> b/linux-user/host/x86_64/host-signal.h
> index 883d2fcf65..c71d597eb2 100644
> --- a/linux-user/host/x86_64/host-signal.h
> +++ b/linux-user/host/x86_64/host-signal.h
> @@ -15,6 +15,11 @@ static inline uintptr_t host_signal_pc(ucontext_t *uc)
>      return uc->uc_mcontext.gregs[REG_RIP];
>  }
>
> +static inline void host_signal_set_pc(ucontext_t *uc, uintptr_t pc)
> +{
> +    uc->uc_mcontext.gregs[REG_RIP] = pc;
> +}
> +
>  static inline bool host_signal_write(siginfo_t *info, ucontext_t *uc)
>  {
>      return uc->uc_mcontext.gregs[REG_TRAPNO] == 0xe
> --
> 2.25.1
>
>

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Re: [PATCH for-6.2 0/2] linux-user: Create a common rewind_if_in_safe_syscall

[Laurent Vivier]

Hi,

Le 22/11/2021 à 14:11, Richard Henderson a écrit :
> This is a re-packaging of two of Warner's patches that
> fix a build issue on aarch64 using musl:
> 
> https://lore.kernel.org/qemu-devel/20211108194230.1836262-1-raj.khem@gmail.com/
> 
> 
> r~
> 
> 
> Warner Losh (2):
>    linux-user: Add host_signal_set_pc to set pc in mcontext
>    linux-user/signal.c: Create a common rewind_if_in_safe_syscall
> 
>   linux-user/host/aarch64/host-signal.h |  5 +++++
>   linux-user/host/aarch64/hostdep.h     | 20 --------------------
>   linux-user/host/alpha/host-signal.h   |  5 +++++
>   linux-user/host/arm/host-signal.h     |  5 +++++
>   linux-user/host/arm/hostdep.h         | 20 --------------------
>   linux-user/host/i386/host-signal.h    |  5 +++++
>   linux-user/host/i386/hostdep.h        | 20 --------------------
>   linux-user/host/mips/host-signal.h    |  5 +++++
>   linux-user/host/ppc/host-signal.h     |  5 +++++
>   linux-user/host/ppc64/hostdep.h       | 20 --------------------
>   linux-user/host/riscv/host-signal.h   |  5 +++++
>   linux-user/host/riscv/hostdep.h       | 20 --------------------
>   linux-user/host/s390/host-signal.h    |  5 +++++
>   linux-user/host/s390x/hostdep.h       | 20 --------------------
>   linux-user/host/sparc/host-signal.h   |  9 +++++++++
>   linux-user/host/x86_64/host-signal.h  |  5 +++++
>   linux-user/host/x86_64/hostdep.h      | 20 --------------------
>   linux-user/safe-syscall.h             |  3 +++
>   linux-user/signal.c                   | 15 ++++++++++++---
>   19 files changed, 69 insertions(+), 143 deletions(-)
> 

Richard, will you take this series via one of your branches or do you want I send a linux-user pull 
request for it?

Thanks,
Laurent

Re: [PATCH for-6.2 0/2] linux-user: Create a common rewind_if_in_safe_syscall

[Richard Henderson]

On 11/22/21 4:43 PM, Laurent Vivier wrote:
> Hi,
> 
> Le 22/11/2021 à 14:11, Richard Henderson a écrit :
>> This is a re-packaging of two of Warner's patches that
>> fix a build issue on aarch64 using musl:
>>
>> https://lore.kernel.org/qemu-devel/20211108194230.1836262-1-raj.khem@gmail.com/
>>
>>
>> r~
>>
>>
>> Warner Losh (2):
>>    linux-user: Add host_signal_set_pc to set pc in mcontext
>>    linux-user/signal.c: Create a common rewind_if_in_safe_syscall
>>
>>   linux-user/host/aarch64/host-signal.h |  5 +++++
>>   linux-user/host/aarch64/hostdep.h     | 20 --------------------
>>   linux-user/host/alpha/host-signal.h   |  5 +++++
>>   linux-user/host/arm/host-signal.h     |  5 +++++
>>   linux-user/host/arm/hostdep.h         | 20 --------------------
>>   linux-user/host/i386/host-signal.h    |  5 +++++
>>   linux-user/host/i386/hostdep.h        | 20 --------------------
>>   linux-user/host/mips/host-signal.h    |  5 +++++
>>   linux-user/host/ppc/host-signal.h     |  5 +++++
>>   linux-user/host/ppc64/hostdep.h       | 20 --------------------
>>   linux-user/host/riscv/host-signal.h   |  5 +++++
>>   linux-user/host/riscv/hostdep.h       | 20 --------------------
>>   linux-user/host/s390/host-signal.h    |  5 +++++
>>   linux-user/host/s390x/hostdep.h       | 20 --------------------
>>   linux-user/host/sparc/host-signal.h   |  9 +++++++++
>>   linux-user/host/x86_64/host-signal.h  |  5 +++++
>>   linux-user/host/x86_64/hostdep.h      | 20 --------------------
>>   linux-user/safe-syscall.h             |  3 +++
>>   linux-user/signal.c                   | 15 ++++++++++++---
>>   19 files changed, 69 insertions(+), 143 deletions(-)
>>
> 
> Richard, will you take this series via one of your branches or do you want I send a 
> linux-user pull request for it?

I have nothing pending myself, but I can send this if you'd like.  I mostly wanted your 
ack on it.

r~

Re: [PATCH for-6.2 0/2] linux-user: Create a common rewind_if_in_safe_syscall

[Laurent Vivier]

Le 22/11/2021 à 16:50, Richard Henderson a écrit :
> On 11/22/21 4:43 PM, Laurent Vivier wrote:
>> Hi,
>>
>> Le 22/11/2021 à 14:11, Richard Henderson a écrit :
>>> This is a re-packaging of two of Warner's patches that
>>> fix a build issue on aarch64 using musl:
>>>
>>> https://lore.kernel.org/qemu-devel/20211108194230.1836262-1-raj.khem@gmail.com/
>>>
>>>
>>> r~
>>>
>>>
>>> Warner Losh (2):
>>>    linux-user: Add host_signal_set_pc to set pc in mcontext
>>>    linux-user/signal.c: Create a common rewind_if_in_safe_syscall
>>>
>>>   linux-user/host/aarch64/host-signal.h |  5 +++++
>>>   linux-user/host/aarch64/hostdep.h     | 20 --------------------
>>>   linux-user/host/alpha/host-signal.h   |  5 +++++
>>>   linux-user/host/arm/host-signal.h     |  5 +++++
>>>   linux-user/host/arm/hostdep.h         | 20 --------------------
>>>   linux-user/host/i386/host-signal.h    |  5 +++++
>>>   linux-user/host/i386/hostdep.h        | 20 --------------------
>>>   linux-user/host/mips/host-signal.h    |  5 +++++
>>>   linux-user/host/ppc/host-signal.h     |  5 +++++
>>>   linux-user/host/ppc64/hostdep.h       | 20 --------------------
>>>   linux-user/host/riscv/host-signal.h   |  5 +++++
>>>   linux-user/host/riscv/hostdep.h       | 20 --------------------
>>>   linux-user/host/s390/host-signal.h    |  5 +++++
>>>   linux-user/host/s390x/hostdep.h       | 20 --------------------
>>>   linux-user/host/sparc/host-signal.h   |  9 +++++++++
>>>   linux-user/host/x86_64/host-signal.h  |  5 +++++
>>>   linux-user/host/x86_64/hostdep.h      | 20 --------------------
>>>   linux-user/safe-syscall.h             |  3 +++
>>>   linux-user/signal.c                   | 15 ++++++++++++---
>>>   19 files changed, 69 insertions(+), 143 deletions(-)
>>>
>>
>> Richard, will you take this series via one of your branches or do you want I send a linux-user 
>> pull request for it?
> 
> I have nothing pending myself, but I can send this if you'd like.  I mostly wanted your ack on it.

Acked-by: Laurent Vivier <laurent@vivier.eu>

Thanks,
Laurent