[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[RFC PATCH 7/7] linux-user: Reorg cpu_signal_handler
|
From: |
Richard Henderson |
|
Subject: |
[RFC PATCH 7/7] linux-user: Reorg cpu_signal_handler |
|
Date: |
Mon, 13 Sep 2021 15:05:52 -0700 |
Split out two functions into linux-user/host/arch/host-signal.h.
Since linux-user requires a linux host, drop all of the BSD and
Solaris ifdefs. These should be recreated under bsd-user/ when
the current blanks there are filled.
Fold the remnants of handle_cpu_signal into host_signal_handler.
Drop the call to cc->tcg_ops->tlb_fill. This was simply an indirect
method to raise SIGSEGV; it is far easier to pass the host siginfo_t
along to the guest. This fixes all of the guest cpu_loop code that
currently fails to properly fill in SEGV_MAPERR vs SEGV_ACCERR.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
include/exec/exec-all.h | 12 -
linux-user/host/aarch64/host-signal.h | 73 +++
linux-user/host/alpha/host-signal.h | 41 ++
linux-user/host/arm/host-signal.h | 30 ++
linux-user/host/i386/host-signal.h | 24 +
linux-user/host/mips/host-signal.h | 61 +++
linux-user/host/ppc/host-signal.h | 24 +
linux-user/host/ppc64/host-signal.h | 1 +
linux-user/host/riscv32/host-signal.h | 57 +++
linux-user/host/riscv64/host-signal.h | 1 +
linux-user/host/s390/host-signal.h | 92 ++++
linux-user/host/s390x/host-signal.h | 1 +
linux-user/host/sparc/host-signal.h | 53 ++
linux-user/host/sparc64/host-signal.h | 1 +
linux-user/host/x86_64/host-signal.h | 24 +
accel/tcg/user-exec.c | 712 --------------------------
linux-user/signal.c | 93 ++--
17 files changed, 543 insertions(+), 757 deletions(-)
create mode 100644 linux-user/host/aarch64/host-signal.h
create mode 100644 linux-user/host/alpha/host-signal.h
create mode 100644 linux-user/host/arm/host-signal.h
create mode 100644 linux-user/host/i386/host-signal.h
create mode 100644 linux-user/host/mips/host-signal.h
create mode 100644 linux-user/host/ppc/host-signal.h
create mode 100644 linux-user/host/ppc64/host-signal.h
create mode 100644 linux-user/host/riscv32/host-signal.h
create mode 100644 linux-user/host/riscv64/host-signal.h
create mode 100644 linux-user/host/s390/host-signal.h
create mode 100644 linux-user/host/s390x/host-signal.h
create mode 100644 linux-user/host/sparc/host-signal.h
create mode 100644 linux-user/host/sparc64/host-signal.h
create mode 100644 linux-user/host/x86_64/host-signal.h
diff --git a/include/exec/exec-all.h b/include/exec/exec-all.h
index f582d3e688..addcec6381 100644
--- a/include/exec/exec-all.h
+++ b/include/exec/exec-all.h
@@ -683,18 +683,6 @@ uintptr_t adjust_signal_pc(uintptr_t pc);
bool handle_sigsegv_accerr_write(CPUState *cpu, sigset_t *old_set,
uintptr_t host_pc, uintptr_t host_addr);
-/**
- * cpu_signal_handler
- * @signum: host signal number
- * @pinfo: host siginfo_t
- * @puc: host ucontext_t
- *
- * To be called from the SIGBUS and SIGSEGV signal handler to inform the
- * virtual cpu of exceptions. Returns true if the signal was handled by
- * the virtual CPU.
- */
-int cpu_signal_handler(int signum, void *pinfo, void *puc);
-
#else
static inline void mmap_lock(void) {}
static inline void mmap_unlock(void) {}
diff --git a/linux-user/host/aarch64/host-signal.h
b/linux-user/host/aarch64/host-signal.h
new file mode 100644
index 0000000000..818da17a21
--- /dev/null
+++ b/linux-user/host/aarch64/host-signal.h
@@ -0,0 +1,73 @@
+/*
+ * host-signal.h: signal info dependent on the host architecture
+ *
+ * Copyright (C) 2021 Linaro Limited
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#ifndef AARCH64_HOST_SIGNAL_H
+#define AARCH64_HOST_SIGNAL_H
+
+/* Pre-3.16 kernel headers don't have these, so provide fallback definitions */
+#ifndef ESR_MAGIC
+#define ESR_MAGIC 0x45535201
+struct esr_context {
+ struct _aarch64_ctx head;
+ uint64_t esr;
+};
+#endif
+
+static inline struct _aarch64_ctx *first_ctx(ucontext_t *uc)
+{
+ return (struct _aarch64_ctx *)&uc->uc_mcontext.__reserved;
+}
+
+static inline struct _aarch64_ctx *next_ctx(struct _aarch64_ctx *hdr)
+{
+ return (struct _aarch64_ctx *)((char *)hdr + hdr->size);
+}
+
+static inline uintptr_t host_signal_pc(ucontext_t *uc)
+{
+ return uc->uc_mcontext.pc;
+}
+
+static inline bool host_sigsegv_write(siginfo_t *info, ucontext_t *uc)
+{
+ struct _aarch64_ctx *hdr;
+ uint32_t insn;
+
+ /* Find the esr_context, which has the WnR bit in it */
+ for (hdr = first_ctx(uc); hdr->magic; hdr = next_ctx(hdr)) {
+ if (hdr->magic == ESR_MAGIC) {
+ struct esr_context const *esrctx = (struct esr_context const *)hdr;
+ uint64_t esr = esrctx->esr;
+
+ /* For data aborts ESR.EC is 0b10010x: then bit 6 is the WnR bit */
+ return extract32(esr, 27, 5) == 0x12 && extract32(esr, 6, 1) == 1;
+ }
+ }
+
+ /*
+ * Fall back to parsing instructions; will only be needed
+ * for really ancient (pre-3.16) kernels.
+ */
+ insn = *(uint32_t *)host_signal_pc(uc);
+
+ return (insn & 0xbfff0000) == 0x0c000000 /* C3.3.1 */
+ || (insn & 0xbfe00000) == 0x0c800000 /* C3.3.2 */
+ || (insn & 0xbfdf0000) == 0x0d000000 /* C3.3.3 */
+ || (insn & 0xbfc00000) == 0x0d800000 /* C3.3.4 */
+ || (insn & 0x3f400000) == 0x08000000 /* C3.3.6 */
+ || (insn & 0x3bc00000) == 0x39000000 /* C3.3.13 */
+ || (insn & 0x3fc00000) == 0x3d800000 /* ... 128bit */
+ /* Ignore bits 10, 11 & 21, controlling indexing. */
+ || (insn & 0x3bc00000) == 0x38000000 /* C3.3.8-12 */
+ || (insn & 0x3fe00000) == 0x3c800000 /* ... 128bit */
+ /* Ignore bits 23 & 24, controlling indexing. */
+ || (insn & 0x3a400000) == 0x28000000; /* C3.3.7,14-16 */
+}
+
+#endif
diff --git a/linux-user/host/alpha/host-signal.h
b/linux-user/host/alpha/host-signal.h
new file mode 100644
index 0000000000..eaf83added
--- /dev/null
+++ b/linux-user/host/alpha/host-signal.h
@@ -0,0 +1,41 @@
+/*
+ * host-signal.h: signal info dependent on the host architecture
+ *
+ * Copyright (C) 2021 Linaro Limited
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#ifndef ALPHA_HOST_SIGNAL_H
+#define ALPHA_HOST_SIGNAL_H
+
+static inline uintptr_t host_signal_pc(ucontext_t *uc)
+{
+ return uc->uc_mcontext.sc_pc;
+}
+
+static inline bool host_sigsegv_write(siginfo_t *info, ucontext_t *uc)
+{
+ uint32_t *pc = uc->uc_mcontext.sc_pc;
+ uint32_t insn = *pc;
+
+ /* XXX: need kernel patch to get write flag faster */
+ switch (insn >> 26) {
+ case 0x0d: /* stw */
+ case 0x0e: /* stb */
+ case 0x0f: /* stq_u */
+ case 0x24: /* stf */
+ case 0x25: /* stg */
+ case 0x26: /* sts */
+ case 0x27: /* stt */
+ case 0x2c: /* stl */
+ case 0x2d: /* stq */
+ case 0x2e: /* stl_c */
+ case 0x2f: /* stq_c */
+ return true;
+ }
+ return false;
+}
+
+#endif
diff --git a/linux-user/host/arm/host-signal.h
b/linux-user/host/arm/host-signal.h
new file mode 100644
index 0000000000..ae6bcde6c1
--- /dev/null
+++ b/linux-user/host/arm/host-signal.h
@@ -0,0 +1,30 @@
+/*
+ * host-signal.h: signal info dependent on the host architecture
+ *
+ * Copyright (C) 2021 Linaro Limited
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#ifndef ARM_HOST_SIGNAL_H
+#define ARM_HOST_SIGNAL_H
+
+static inline uintptr_t host_signal_pc(ucontext_t *uc)
+{
+ return uc->uc_mcontext.gregs[R15];
+}
+
+static inline bool host_sigsegv_write(siginfo_t *info, ucontext_t *uc,
+ uintptr_t pc)
+{
+ /*
+ * In the FSR, bit 11 is WnR, assuming a v6 or
+ * later processor. On v5 we will always report
+ * this as a read, which will fail later.
+ */
+ uint32_t fsr = uc->uc_mcontext.error_code;
+ return extract32(fsr, 11, 1);
+}
+
+#endif
diff --git a/linux-user/host/i386/host-signal.h
b/linux-user/host/i386/host-signal.h
new file mode 100644
index 0000000000..a8ca5e4a89
--- /dev/null
+++ b/linux-user/host/i386/host-signal.h
@@ -0,0 +1,24 @@
+/*
+ * host-signal.h: signal info dependent on the host architecture
+ *
+ * Copyright (C) 2021 Linaro Limited
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#ifndef I386_HOST_SIGNAL_H
+#define I386_HOST_SIGNAL_H
+
+static inline uintptr_t host_signal_pc(ucontext_t *uc)
+{
+ return uc->uc_mcontext.gregs[REG_EIP];
+}
+
+static inline bool host_sigsegv_write(siginfo_t *info, ucontext_t *uc)
+{
+ return uc->uc_mcontext.gregs[REG_TRAPNO] == 0xe
+ && (uc->uc_mcontext.gregs[REG_ERR] & 0x2);
+}
+
+#endif
diff --git a/linux-user/host/mips/host-signal.h
b/linux-user/host/mips/host-signal.h
new file mode 100644
index 0000000000..815bbd61fa
--- /dev/null
+++ b/linux-user/host/mips/host-signal.h
@@ -0,0 +1,61 @@
+/*
+ * host-signal.h: signal info dependent on the host architecture
+ *
+ * Copyright (C) 2021 Linaro Limited
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#ifndef MIPS_HOST_SIGNAL_H
+#define MIPS_HOST_SIGNAL_H
+
+static inline uintptr_t host_signal_pc(ucontext_t *uc)
+{
+ return uc->uc_mcontext.pc;
+}
+
+#if defined(__misp16) || defined(__mips_micromips)
+#error "Unsupported encoding"
+#endif
+
+static inline bool host_sigsegv_write(siginfo_t *info, ucontext_t *uc)
+{
+ uint32_t *insn = *(uint32_t *)host_signal_pc(uc);
+
+ /* Detect all store instructions at program counter. */
+ switch ((insn >> 26) & 077) {
+ case 050: /* SB */
+ case 051: /* SH */
+ case 052: /* SWL */
+ case 053: /* SW */
+ case 054: /* SDL */
+ case 055: /* SDR */
+ case 056: /* SWR */
+ case 070: /* SC */
+ case 071: /* SWC1 */
+ case 074: /* SCD */
+ case 075: /* SDC1 */
+ case 077: /* SD */
+#if !defined(__mips_isa_rev) || __mips_isa_rev < 6
+ case 072: /* SWC2 */
+ case 076: /* SDC2 */
+#endif
+ return true;
+ case 023: /* COP1X */
+ /*
+ * Required in all versions of MIPS64 since
+ * MIPS64r1 and subsequent versions of MIPS32r2.
+ */
+ switch (insn & 077) {
+ case 010: /* SWXC1 */
+ case 011: /* SDXC1 */
+ case 015: /* SUXC1 */
+ return true;
+ }
+ break;
+ }
+ return false;
+}
+
+#endif
diff --git a/linux-user/host/ppc/host-signal.h
b/linux-user/host/ppc/host-signal.h
new file mode 100644
index 0000000000..b8dce622b4
--- /dev/null
+++ b/linux-user/host/ppc/host-signal.h
@@ -0,0 +1,24 @@
+/*
+ * host-signal.h: signal info dependent on the host architecture
+ *
+ * Copyright (C) 2021 Linaro Limited
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#ifndef PPC_HOST_SIGNAL_H
+#define PPC_HOST_SIGNAL_H
+
+static inline uintptr_t host_signal_pc(ucontext_t *uc)
+{
+ return uc->uc_mcontext.regs->nip;
+}
+
+static inline bool host_sigsegv_write(siginfo_t *info, ucontext_t *uc)
+{
+ return uc->uc_mcontext.regs->trap != 0x400
+ && (uc->uc_mcontext.regs->dsisr & 0x02000000);
+}
+
+#endif
diff --git a/linux-user/host/ppc64/host-signal.h
b/linux-user/host/ppc64/host-signal.h
new file mode 100644
index 0000000000..a353c22a90
--- /dev/null
+++ b/linux-user/host/ppc64/host-signal.h
@@ -0,0 +1 @@
+#include "../ppc/host-signal.h"
diff --git a/linux-user/host/riscv32/host-signal.h
b/linux-user/host/riscv32/host-signal.h
new file mode 100644
index 0000000000..f877412f96
--- /dev/null
+++ b/linux-user/host/riscv32/host-signal.h
@@ -0,0 +1,57 @@
+/*
+ * host-signal.h: signal info dependent on the host architecture
+ *
+ * Copyright (C) 2021 Linaro Limited
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#ifndef RISCV_HOST_SIGNAL_H
+#define RISCV_HOST_SIGNAL_H
+
+static inline uintptr_t host_signal_pc(ucontext_t *uc)
+{
+ return uc->uc_mcontext.__gregs[REG_PC];
+}
+
+static inline bool host_sigsegv_write(siginfo_t *info, ucontext_t *uc)
+{
+ /*
+ * Detect store by reading the instruction at the program counter.
+ * Do not read more than 16 bits, because we have not yet determined
+ * the size of the instruction.
+ */
+ const uint16_t *pinsn = (const uint16_t *)host_signal_pc(uc);
+ uint16_t insn = pinsn[0];
+
+ /* 16-bit instructions */
+ switch (insn & 0xe003) {
+ case 0xa000: /* c.fsd */
+ case 0xc000: /* c.sw */
+ case 0xe000: /* c.sd (rv64) / c.fsw (rv32) */
+ case 0xa002: /* c.fsdsp */
+ case 0xc002: /* c.swsp */
+ case 0xe002: /* c.sdsp (rv64) / c.fswsp (rv32) */
+ return true;
+ }
+
+ /* 32-bit instructions, major opcodes */
+ switch (insn & 0x7f) {
+ case 0x23: /* store */
+ case 0x27: /* store-fp */
+ return true;
+ case 0x2f: /* amo */
+ /*
+ * The AMO function code is in bits 25-31, unread as yet.
+ * The AMO functions are LR (read), SC (write), and the
+ * rest are all read-modify-write.
+ */
+ insn = pinsn[1];
+ return (insn >> 11) != 2; /* LR */
+ }
+
+ return false;
+}
+
+#endif
diff --git a/linux-user/host/riscv64/host-signal.h
b/linux-user/host/riscv64/host-signal.h
new file mode 100644
index 0000000000..6e27f725ab
--- /dev/null
+++ b/linux-user/host/riscv64/host-signal.h
@@ -0,0 +1 @@
+#include "../riscv32/host-signal.h"
diff --git a/linux-user/host/s390/host-signal.h
b/linux-user/host/s390/host-signal.h
new file mode 100644
index 0000000000..8d34b32b9f
--- /dev/null
+++ b/linux-user/host/s390/host-signal.h
@@ -0,0 +1,92 @@
+/*
+ * host-signal.h: signal info dependent on the host architecture
+ *
+ * Copyright (C) 2021 Linaro Limited
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#ifndef S390_HOST_SIGNAL_H
+#define S390_HOST_SIGNAL_H
+
+static inline uintptr_t host_signal_pc(ucontext_t *uc)
+{
+ return uc->uc_mcontext.psw.addr;
+}
+
+static inline bool host_sigsegv_write(siginfo_t *info, ucontext_t *uc)
+{
+ uint16_t *pinsn = (uint16_t *)host_signal_pc(uc);
+
+ /*
+ * ??? On linux, the non-rt signal handler has 4 (!) arguments instead
+ * of the normal 2 arguments. The 4th argument contains the "Translation-
+ * Exception Identification for DAT Exceptions" from the hardware (aka
+ * "int_parm_long"), which does in fact contain the is_write value.
+ * The rt signal handler, as far as I can tell, does not give this value
+ * at all. Not that we could get to it from here even if it were.
+ * So fall back to parsing instructions. Treat read-modify-write ones as
+ * writes, which is not fully correct, but for tracking self-modifying code
+ * this is better than treating them as reads. Checking si_addr page flags
+ * might be a viable improvement, albeit a racy one.
+ */
+ /* ??? This is not even close to complete. */
+ switch (pinsn[0] >> 8) {
+ case 0x50: /* ST */
+ case 0x42: /* STC */
+ case 0x40: /* STH */
+ case 0xba: /* CS */
+ case 0xbb: /* CDS */
+ return true;
+ case 0xc4: /* RIL format insns */
+ switch (pinsn[0] & 0xf) {
+ case 0xf: /* STRL */
+ case 0xb: /* STGRL */
+ case 0x7: /* STHRL */
+ return true;
+ }
+ break;
+ case 0xc8: /* SSF format insns */
+ switch (pinsn[0] & 0xf) {
+ case 0x2: /* CSST */
+ return true;
+ }
+ break;
+ case 0xe3: /* RXY format insns */
+ switch (pinsn[2] & 0xff) {
+ case 0x50: /* STY */
+ case 0x24: /* STG */
+ case 0x72: /* STCY */
+ case 0x70: /* STHY */
+ case 0x8e: /* STPQ */
+ case 0x3f: /* STRVH */
+ case 0x3e: /* STRV */
+ case 0x2f: /* STRVG */
+ return true;
+ }
+ break;
+ case 0xeb: /* RSY format insns */
+ switch (pinsn[2] & 0xff) {
+ case 0x14: /* CSY */
+ case 0x30: /* CSG */
+ case 0x31: /* CDSY */
+ case 0x3e: /* CDSG */
+ case 0xe4: /* LANG */
+ case 0xe6: /* LAOG */
+ case 0xe7: /* LAXG */
+ case 0xe8: /* LAAG */
+ case 0xea: /* LAALG */
+ case 0xf4: /* LAN */
+ case 0xf6: /* LAO */
+ case 0xf7: /* LAX */
+ case 0xfa: /* LAAL */
+ case 0xf8: /* LAA */
+ return true;
+ }
+ break;
+ }
+ return false;
+}
+
+#endif
diff --git a/linux-user/host/s390x/host-signal.h
b/linux-user/host/s390x/host-signal.h
new file mode 100644
index 0000000000..0e83f9358d
--- /dev/null
+++ b/linux-user/host/s390x/host-signal.h
@@ -0,0 +1 @@
+#include "../s390/host-signal.h"
diff --git a/linux-user/host/sparc/host-signal.h
b/linux-user/host/sparc/host-signal.h
new file mode 100644
index 0000000000..47d3b1512e
--- /dev/null
+++ b/linux-user/host/sparc/host-signal.h
@@ -0,0 +1,53 @@
+/*
+ * host-signal.h: signal info dependent on the host architecture
+ *
+ * Copyright (C) 2021 Linaro Limited
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#ifndef SPARC_HOST_SIGNAL_H
+#define SPARC_HOST_SIGNAL_H
+
+static inline uintptr_t host_signal_pc(ucontext_t *uc)
+{
+#ifdef __arch64__
+ return uc->uc_mcontext.mc_gregs[MC_PC];
+#else
+ return uc->uc_mcontext.gregs[REG_PC];
+#endif
+}
+
+static inline bool host_sigsegv_write(siginfo_t *info, ucontext_t *uc)
+{
+ uint32_t insn = *(uint32_t *)host_signal_pc(uc);
+
+ if ((insn >> 30) == 3) {
+ switch ((insn >> 19) & 0x3f) {
+ case 0x05: /* stb */
+ case 0x15: /* stba */
+ case 0x06: /* sth */
+ case 0x16: /* stha */
+ case 0x04: /* st */
+ case 0x14: /* sta */
+ case 0x07: /* std */
+ case 0x17: /* stda */
+ case 0x0e: /* stx */
+ case 0x1e: /* stxa */
+ case 0x24: /* stf */
+ case 0x34: /* stfa */
+ case 0x27: /* stdf */
+ case 0x37: /* stdfa */
+ case 0x26: /* stqf */
+ case 0x36: /* stqfa */
+ case 0x25: /* stfsr */
+ case 0x3c: /* casa */
+ case 0x3e: /* casxa */
+ return true;
+ }
+ }
+ return false;
+}
+
+#endif
diff --git a/linux-user/host/sparc64/host-signal.h
b/linux-user/host/sparc64/host-signal.h
new file mode 100644
index 0000000000..1191fe2d40
--- /dev/null
+++ b/linux-user/host/sparc64/host-signal.h
@@ -0,0 +1 @@
+#include "../sparc/host-signal.h"
diff --git a/linux-user/host/x86_64/host-signal.h
b/linux-user/host/x86_64/host-signal.h
new file mode 100644
index 0000000000..d5fb3e4484
--- /dev/null
+++ b/linux-user/host/x86_64/host-signal.h
@@ -0,0 +1,24 @@
+/*
+ * host-signal.h: signal info dependent on the host architecture
+ *
+ * Copyright (C) 2021 Linaro Limited
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#ifndef X86_64_HOST_SIGNAL_H
+#define X86_64_HOST_SIGNAL_H
+
+static inline uintptr_t host_signal_pc(ucontext_t *uc)
+{
+ return uc->uc_mcontext.gregs[REG_RIP];
+}
+
+static inline bool host_sigsegv_write(siginfo_t *info, ucontext_t *uc)
+{
+ return uc->uc_mcontext.gregs[REG_TRAPNO] == 0xe
+ && (uc->uc_mcontext.gregs[REG_ERR] & 0x2);
+}
+
+#endif
diff --git a/accel/tcg/user-exec.c b/accel/tcg/user-exec.c
index ad6b4f6abf..39635cbea2 100644
--- a/accel/tcg/user-exec.c
+++ b/accel/tcg/user-exec.c
@@ -29,23 +29,8 @@
#include "trace/trace-root.h"
#include "trace/mem.h"
-#undef EAX
-#undef ECX
-#undef EDX
-#undef EBX
-#undef ESP
-#undef EBP
-#undef ESI
-#undef EDI
-#undef EIP
-#ifdef __linux__
-#include <sys/ucontext.h>
-#endif
-
__thread uintptr_t helper_retaddr;
-//#define DEBUG_SIGNAL
-
/**
* adjust_signal_pc:
* @pc: raw pc from the host signal ucontext_t.
@@ -154,69 +139,6 @@ bool handle_sigsegv_accerr_write(CPUState *cpu, sigset_t
*old_set,
}
}
-/* 'pc' is the host PC at which the exception was raised. 'address' is
- the effective address of the memory exception. 'is_write' is 1 if a
- write caused the exception and otherwise 0'. 'old_set' is the
- signal set which should be restored */
-static inline int handle_cpu_signal(uintptr_t pc, siginfo_t *info,
- int is_write, sigset_t *old_set)
-{
- CPUState *cpu = current_cpu;
- CPUClass *cc;
- unsigned long address = (unsigned long)info->si_addr;
- MMUAccessType access_type;
-
- if (is_write) {
- access_type = MMU_DATA_STORE;
- } else if (helper_retaddr == 1) {
- access_type = MMU_INST_FETCH;
- } else {
- access_type = MMU_DATA_LOAD;
- }
- pc = adjust_signal_pc(pc);
-
- /* For synchronous signals we expect to be coming from the vCPU
- * thread (so current_cpu should be valid) and either from running
- * code or during translation which can fault as we cross pages.
- *
- * If neither is true then something has gone wrong and we should
- * abort rather than try and restart the vCPU execution.
- */
- if (!cpu || !cpu->running) {
- printf("qemu:%s received signal outside vCPU context @ pc=0x%"
- PRIxPTR "\n", __func__, pc);
- abort();
- }
-
-#if defined(DEBUG_SIGNAL)
- printf("qemu: SIGSEGV pc=0x%08lx address=%08lx w=%d oldset=0x%08lx\n",
- pc, address, is_write, *(unsigned long *)old_set);
-#endif
-
- /* XXX: locking issue */
- if (is_write &&
- info->si_signo == SIGSEGV &&
- info->si_code == SEGV_ACCERR &&
- handle_sigsegv_accerr_write(cpu, old_set, pc, address)) {
- return 1;
- }
-
- /* Convert forcefully to guest address space, invalid addresses
- are still valid segv ones */
- address = h2g_nocheck(address);
-
- /*
- * There is no way the target can handle this other than raising
- * an exception. Undo signal and retaddr state prior to longjmp.
- */
- sigprocmask(SIG_SETMASK, old_set, NULL);
-
- cc = CPU_GET_CLASS(cpu);
- cc->tcg_ops->tlb_fill(cpu, address, 0, access_type,
- MMU_USER_IDX, false, pc);
- g_assert_not_reached();
-}
-
static int probe_access_internal(CPUArchState *env, target_ulong addr,
int fault_size, MMUAccessType access_type,
bool nonfault, uintptr_t ra)
@@ -275,640 +197,6 @@ void *probe_access(CPUArchState *env, target_ulong addr,
int size,
return size ? g2h(env_cpu(env), addr) : NULL;
}
-#if defined(__i386__)
-
-#if defined(__NetBSD__)
-#include <ucontext.h>
-#include <machine/trap.h>
-
-#define EIP_sig(context) ((context)->uc_mcontext.__gregs[_REG_EIP])
-#define TRAP_sig(context) ((context)->uc_mcontext.__gregs[_REG_TRAPNO])
-#define ERROR_sig(context) ((context)->uc_mcontext.__gregs[_REG_ERR])
-#define MASK_sig(context) ((context)->uc_sigmask)
-#define PAGE_FAULT_TRAP T_PAGEFLT
-#elif defined(__FreeBSD__) || defined(__DragonFly__)
-#include <ucontext.h>
-#include <machine/trap.h>
-
-#define EIP_sig(context) (*((unsigned long *)&(context)->uc_mcontext.mc_eip))
-#define TRAP_sig(context) ((context)->uc_mcontext.mc_trapno)
-#define ERROR_sig(context) ((context)->uc_mcontext.mc_err)
-#define MASK_sig(context) ((context)->uc_sigmask)
-#define PAGE_FAULT_TRAP T_PAGEFLT
-#elif defined(__OpenBSD__)
-#include <machine/trap.h>
-#define EIP_sig(context) ((context)->sc_eip)
-#define TRAP_sig(context) ((context)->sc_trapno)
-#define ERROR_sig(context) ((context)->sc_err)
-#define MASK_sig(context) ((context)->sc_mask)
-#define PAGE_FAULT_TRAP T_PAGEFLT
-#else
-#define EIP_sig(context) ((context)->uc_mcontext.gregs[REG_EIP])
-#define TRAP_sig(context) ((context)->uc_mcontext.gregs[REG_TRAPNO])
-#define ERROR_sig(context) ((context)->uc_mcontext.gregs[REG_ERR])
-#define MASK_sig(context) ((context)->uc_sigmask)
-#define PAGE_FAULT_TRAP 0xe
-#endif
-
-int cpu_signal_handler(int host_signum, void *pinfo,
- void *puc)
-{
- siginfo_t *info = pinfo;
-#if defined(__NetBSD__) || defined(__FreeBSD__) || defined(__DragonFly__)
- ucontext_t *uc = puc;
-#elif defined(__OpenBSD__)
- struct sigcontext *uc = puc;
-#else
- ucontext_t *uc = puc;
-#endif
- unsigned long pc;
- int trapno;
-
-#ifndef REG_EIP
-/* for glibc 2.1 */
-#define REG_EIP EIP
-#define REG_ERR ERR
-#define REG_TRAPNO TRAPNO
-#endif
- pc = EIP_sig(uc);
- trapno = TRAP_sig(uc);
- return handle_cpu_signal(pc, info,
- trapno == PAGE_FAULT_TRAP ?
- (ERROR_sig(uc) >> 1) & 1 : 0,
- &MASK_sig(uc));
-}
-
-#elif defined(__x86_64__)
-
-#ifdef __NetBSD__
-#include <machine/trap.h>
-#define PC_sig(context) _UC_MACHINE_PC(context)
-#define TRAP_sig(context) ((context)->uc_mcontext.__gregs[_REG_TRAPNO])
-#define ERROR_sig(context) ((context)->uc_mcontext.__gregs[_REG_ERR])
-#define MASK_sig(context) ((context)->uc_sigmask)
-#define PAGE_FAULT_TRAP T_PAGEFLT
-#elif defined(__OpenBSD__)
-#include <machine/trap.h>
-#define PC_sig(context) ((context)->sc_rip)
-#define TRAP_sig(context) ((context)->sc_trapno)
-#define ERROR_sig(context) ((context)->sc_err)
-#define MASK_sig(context) ((context)->sc_mask)
-#define PAGE_FAULT_TRAP T_PAGEFLT
-#elif defined(__FreeBSD__) || defined(__DragonFly__)
-#include <ucontext.h>
-#include <machine/trap.h>
-
-#define PC_sig(context) (*((unsigned long *)&(context)->uc_mcontext.mc_rip))
-#define TRAP_sig(context) ((context)->uc_mcontext.mc_trapno)
-#define ERROR_sig(context) ((context)->uc_mcontext.mc_err)
-#define MASK_sig(context) ((context)->uc_sigmask)
-#define PAGE_FAULT_TRAP T_PAGEFLT
-#else
-#define PC_sig(context) ((context)->uc_mcontext.gregs[REG_RIP])
-#define TRAP_sig(context) ((context)->uc_mcontext.gregs[REG_TRAPNO])
-#define ERROR_sig(context) ((context)->uc_mcontext.gregs[REG_ERR])
-#define MASK_sig(context) ((context)->uc_sigmask)
-#define PAGE_FAULT_TRAP 0xe
-#endif
-
-int cpu_signal_handler(int host_signum, void *pinfo,
- void *puc)
-{
- siginfo_t *info = pinfo;
- unsigned long pc;
-#if defined(__NetBSD__) || defined(__FreeBSD__) || defined(__DragonFly__)
- ucontext_t *uc = puc;
-#elif defined(__OpenBSD__)
- struct sigcontext *uc = puc;
-#else
- ucontext_t *uc = puc;
-#endif
-
- pc = PC_sig(uc);
- return handle_cpu_signal(pc, info,
- TRAP_sig(uc) == PAGE_FAULT_TRAP ?
- (ERROR_sig(uc) >> 1) & 1 : 0,
- &MASK_sig(uc));
-}
-
-#elif defined(_ARCH_PPC)
-
-/***********************************************************************
- * signal context platform-specific definitions
- * From Wine
- */
-#ifdef linux
-/* All Registers access - only for local access */
-#define REG_sig(reg_name, context) \
- ((context)->uc_mcontext.regs->reg_name)
-/* Gpr Registers access */
-#define GPR_sig(reg_num, context) REG_sig(gpr[reg_num], context)
-/* Program counter */
-#define IAR_sig(context) REG_sig(nip, context)
-/* Machine State Register (Supervisor) */
-#define MSR_sig(context) REG_sig(msr, context)
-/* Count register */
-#define CTR_sig(context) REG_sig(ctr, context)
-/* User's integer exception register */
-#define XER_sig(context) REG_sig(xer, context)
-/* Link register */
-#define LR_sig(context) REG_sig(link, context)
-/* Condition register */
-#define CR_sig(context) REG_sig(ccr, context)
-
-/* Float Registers access */
-#define FLOAT_sig(reg_num, context) \
- (((double *)((char *)((context)->uc_mcontext.regs + 48 * 4)))[reg_num])
-#define FPSCR_sig(context) \
- (*(int *)((char *)((context)->uc_mcontext.regs + (48 + 32 * 2) * 4)))
-/* Exception Registers access */
-#define DAR_sig(context) REG_sig(dar, context)
-#define DSISR_sig(context) REG_sig(dsisr, context)
-#define TRAP_sig(context) REG_sig(trap, context)
-#endif /* linux */
-
-#if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
-#include <ucontext.h>
-#define IAR_sig(context) ((context)->uc_mcontext.mc_srr0)
-#define MSR_sig(context) ((context)->uc_mcontext.mc_srr1)
-#define CTR_sig(context) ((context)->uc_mcontext.mc_ctr)
-#define XER_sig(context) ((context)->uc_mcontext.mc_xer)
-#define LR_sig(context) ((context)->uc_mcontext.mc_lr)
-#define CR_sig(context) ((context)->uc_mcontext.mc_cr)
-/* Exception Registers access */
-#define DAR_sig(context) ((context)->uc_mcontext.mc_dar)
-#define DSISR_sig(context) ((context)->uc_mcontext.mc_dsisr)
-#define TRAP_sig(context) ((context)->uc_mcontext.mc_exc)
-#endif /* __FreeBSD__|| __FreeBSD_kernel__ */
-
-int cpu_signal_handler(int host_signum, void *pinfo,
- void *puc)
-{
- siginfo_t *info = pinfo;
-#if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
- ucontext_t *uc = puc;
-#else
- ucontext_t *uc = puc;
-#endif
- unsigned long pc;
- int is_write;
-
- pc = IAR_sig(uc);
- is_write = 0;
-#if 0
- /* ppc 4xx case */
- if (DSISR_sig(uc) & 0x00800000) {
- is_write = 1;
- }
-#else
- if (TRAP_sig(uc) != 0x400 && (DSISR_sig(uc) & 0x02000000)) {
- is_write = 1;
- }
-#endif
- return handle_cpu_signal(pc, info, is_write, &uc->uc_sigmask);
-}
-
-#elif defined(__alpha__)
-
-int cpu_signal_handler(int host_signum, void *pinfo,
- void *puc)
-{
- siginfo_t *info = pinfo;
- ucontext_t *uc = puc;
- uint32_t *pc = uc->uc_mcontext.sc_pc;
- uint32_t insn = *pc;
- int is_write = 0;
-
- /* XXX: need kernel patch to get write flag faster */
- switch (insn >> 26) {
- case 0x0d: /* stw */
- case 0x0e: /* stb */
- case 0x0f: /* stq_u */
- case 0x24: /* stf */
- case 0x25: /* stg */
- case 0x26: /* sts */
- case 0x27: /* stt */
- case 0x2c: /* stl */
- case 0x2d: /* stq */
- case 0x2e: /* stl_c */
- case 0x2f: /* stq_c */
- is_write = 1;
- }
-
- return handle_cpu_signal(pc, info, is_write, &uc->uc_sigmask);
-}
-#elif defined(__sparc__)
-
-int cpu_signal_handler(int host_signum, void *pinfo,
- void *puc)
-{
- siginfo_t *info = pinfo;
- int is_write;
- uint32_t insn;
-#if !defined(__arch64__) || defined(CONFIG_SOLARIS)
- uint32_t *regs = (uint32_t *)(info + 1);
- void *sigmask = (regs + 20);
- /* XXX: is there a standard glibc define ? */
- unsigned long pc = regs[1];
-#else
-#ifdef __linux__
- struct sigcontext *sc = puc;
- unsigned long pc = sc->sigc_regs.tpc;
- void *sigmask = (void *)sc->sigc_mask;
-#elif defined(__OpenBSD__)
- struct sigcontext *uc = puc;
- unsigned long pc = uc->sc_pc;
- void *sigmask = (void *)(long)uc->sc_mask;
-#elif defined(__NetBSD__)
- ucontext_t *uc = puc;
- unsigned long pc = _UC_MACHINE_PC(uc);
- void *sigmask = (void *)&uc->uc_sigmask;
-#endif
-#endif
-
- /* XXX: need kernel patch to get write flag faster */
- is_write = 0;
- insn = *(uint32_t *)pc;
- if ((insn >> 30) == 3) {
- switch ((insn >> 19) & 0x3f) {
- case 0x05: /* stb */
- case 0x15: /* stba */
- case 0x06: /* sth */
- case 0x16: /* stha */
- case 0x04: /* st */
- case 0x14: /* sta */
- case 0x07: /* std */
- case 0x17: /* stda */
- case 0x0e: /* stx */
- case 0x1e: /* stxa */
- case 0x24: /* stf */
- case 0x34: /* stfa */
- case 0x27: /* stdf */
- case 0x37: /* stdfa */
- case 0x26: /* stqf */
- case 0x36: /* stqfa */
- case 0x25: /* stfsr */
- case 0x3c: /* casa */
- case 0x3e: /* casxa */
- is_write = 1;
- break;
- }
- }
- return handle_cpu_signal(pc, info, is_write, sigmask);
-}
-
-#elif defined(__arm__)
-
-#if defined(__NetBSD__)
-#include <ucontext.h>
-#include <sys/siginfo.h>
-#endif
-
-int cpu_signal_handler(int host_signum, void *pinfo,
- void *puc)
-{
- siginfo_t *info = pinfo;
-#if defined(__NetBSD__)
- ucontext_t *uc = puc;
- siginfo_t *si = pinfo;
-#else
- ucontext_t *uc = puc;
-#endif
- unsigned long pc;
- uint32_t fsr;
- int is_write;
-
-#if defined(__NetBSD__)
- pc = uc->uc_mcontext.__gregs[_REG_R15];
-#elif defined(__GLIBC__) && (__GLIBC__ < 2 || (__GLIBC__ == 2 &&
__GLIBC_MINOR__ <= 3))
- pc = uc->uc_mcontext.gregs[R15];
-#else
- pc = uc->uc_mcontext.arm_pc;
-#endif
-
-#ifdef __NetBSD__
- fsr = si->si_trap;
-#else
- fsr = uc->uc_mcontext.error_code;
-#endif
- /*
- * In the FSR, bit 11 is WnR, assuming a v6 or
- * later processor. On v5 we will always report
- * this as a read, which will fail later.
- */
- is_write = extract32(fsr, 11, 1);
- return handle_cpu_signal(pc, info, is_write, &uc->uc_sigmask);
-}
-
-#elif defined(__aarch64__)
-
-#if defined(__NetBSD__)
-
-#include <ucontext.h>
-#include <sys/siginfo.h>
-
-int cpu_signal_handler(int host_signum, void *pinfo, void *puc)
-{
- ucontext_t *uc = puc;
- siginfo_t *si = pinfo;
- unsigned long pc;
- int is_write;
- uint32_t esr;
-
- pc = uc->uc_mcontext.__gregs[_REG_PC];
- esr = si->si_trap;
-
- /*
- * siginfo_t::si_trap is the ESR value, for data aborts ESR.EC
- * is 0b10010x: then bit 6 is the WnR bit
- */
- is_write = extract32(esr, 27, 5) == 0x12 && extract32(esr, 6, 1) == 1;
- return handle_cpu_signal(pc, si, is_write, &uc->uc_sigmask);
-}
-
-#else
-
-#ifndef ESR_MAGIC
-/* Pre-3.16 kernel headers don't have these, so provide fallback definitions */
-#define ESR_MAGIC 0x45535201
-struct esr_context {
- struct _aarch64_ctx head;
- uint64_t esr;
-};
-#endif
-
-static inline struct _aarch64_ctx *first_ctx(ucontext_t *uc)
-{
- return (struct _aarch64_ctx *)&uc->uc_mcontext.__reserved;
-}
-
-static inline struct _aarch64_ctx *next_ctx(struct _aarch64_ctx *hdr)
-{
- return (struct _aarch64_ctx *)((char *)hdr + hdr->size);
-}
-
-int cpu_signal_handler(int host_signum, void *pinfo, void *puc)
-{
- siginfo_t *info = pinfo;
- ucontext_t *uc = puc;
- uintptr_t pc = uc->uc_mcontext.pc;
- bool is_write;
- struct _aarch64_ctx *hdr;
- struct esr_context const *esrctx = NULL;
-
- /* Find the esr_context, which has the WnR bit in it */
- for (hdr = first_ctx(uc); hdr->magic; hdr = next_ctx(hdr)) {
- if (hdr->magic == ESR_MAGIC) {
- esrctx = (struct esr_context const *)hdr;
- break;
- }
- }
-
- if (esrctx) {
- /* For data aborts ESR.EC is 0b10010x: then bit 6 is the WnR bit */
- uint64_t esr = esrctx->esr;
- is_write = extract32(esr, 27, 5) == 0x12 && extract32(esr, 6, 1) == 1;
- } else {
- /*
- * Fall back to parsing instructions; will only be needed
- * for really ancient (pre-3.16) kernels.
- */
- uint32_t insn = *(uint32_t *)pc;
-
- is_write = ((insn & 0xbfff0000) == 0x0c000000 /* C3.3.1 */
- || (insn & 0xbfe00000) == 0x0c800000 /* C3.3.2 */
- || (insn & 0xbfdf0000) == 0x0d000000 /* C3.3.3 */
- || (insn & 0xbfc00000) == 0x0d800000 /* C3.3.4 */
- || (insn & 0x3f400000) == 0x08000000 /* C3.3.6 */
- || (insn & 0x3bc00000) == 0x39000000 /* C3.3.13 */
- || (insn & 0x3fc00000) == 0x3d800000 /* ... 128bit */
- /* Ignore bits 10, 11 & 21, controlling indexing. */
- || (insn & 0x3bc00000) == 0x38000000 /* C3.3.8-12 */
- || (insn & 0x3fe00000) == 0x3c800000 /* ... 128bit */
- /* Ignore bits 23 & 24, controlling indexing. */
- || (insn & 0x3a400000) == 0x28000000); /* C3.3.7,14-16 */
- }
- return handle_cpu_signal(pc, info, is_write, &uc->uc_sigmask);
-}
-#endif
-
-#elif defined(__s390__)
-
-int cpu_signal_handler(int host_signum, void *pinfo,
- void *puc)
-{
- siginfo_t *info = pinfo;
- ucontext_t *uc = puc;
- unsigned long pc;
- uint16_t *pinsn;
- int is_write = 0;
-
- pc = uc->uc_mcontext.psw.addr;
-
- /*
- * ??? On linux, the non-rt signal handler has 4 (!) arguments instead
- * of the normal 2 arguments. The 4th argument contains the "Translation-
- * Exception Identification for DAT Exceptions" from the hardware (aka
- * "int_parm_long"), which does in fact contain the is_write value.
- * The rt signal handler, as far as I can tell, does not give this value
- * at all. Not that we could get to it from here even if it were.
- * So fall back to parsing instructions. Treat read-modify-write ones as
- * writes, which is not fully correct, but for tracking self-modifying code
- * this is better than treating them as reads. Checking si_addr page flags
- * might be a viable improvement, albeit a racy one.
- */
- /* ??? This is not even close to complete. */
- pinsn = (uint16_t *)pc;
- switch (pinsn[0] >> 8) {
- case 0x50: /* ST */
- case 0x42: /* STC */
- case 0x40: /* STH */
- case 0xba: /* CS */
- case 0xbb: /* CDS */
- is_write = 1;
- break;
- case 0xc4: /* RIL format insns */
- switch (pinsn[0] & 0xf) {
- case 0xf: /* STRL */
- case 0xb: /* STGRL */
- case 0x7: /* STHRL */
- is_write = 1;
- }
- break;
- case 0xc8: /* SSF format insns */
- switch (pinsn[0] & 0xf) {
- case 0x2: /* CSST */
- is_write = 1;
- }
- break;
- case 0xe3: /* RXY format insns */
- switch (pinsn[2] & 0xff) {
- case 0x50: /* STY */
- case 0x24: /* STG */
- case 0x72: /* STCY */
- case 0x70: /* STHY */
- case 0x8e: /* STPQ */
- case 0x3f: /* STRVH */
- case 0x3e: /* STRV */
- case 0x2f: /* STRVG */
- is_write = 1;
- }
- break;
- case 0xeb: /* RSY format insns */
- switch (pinsn[2] & 0xff) {
- case 0x14: /* CSY */
- case 0x30: /* CSG */
- case 0x31: /* CDSY */
- case 0x3e: /* CDSG */
- case 0xe4: /* LANG */
- case 0xe6: /* LAOG */
- case 0xe7: /* LAXG */
- case 0xe8: /* LAAG */
- case 0xea: /* LAALG */
- case 0xf4: /* LAN */
- case 0xf6: /* LAO */
- case 0xf7: /* LAX */
- case 0xfa: /* LAAL */
- case 0xf8: /* LAA */
- is_write = 1;
- }
- break;
- }
-
- return handle_cpu_signal(pc, info, is_write, &uc->uc_sigmask);
-}
-
-#elif defined(__mips__)
-
-#if defined(__misp16) || defined(__mips_micromips)
-#error "Unsupported encoding"
-#endif
-
-int cpu_signal_handler(int host_signum, void *pinfo,
- void *puc)
-{
- siginfo_t *info = pinfo;
- ucontext_t *uc = puc;
- uintptr_t pc = uc->uc_mcontext.pc;
- uint32_t insn = *(uint32_t *)pc;
- int is_write = 0;
-
- /* Detect all store instructions at program counter. */
- switch((insn >> 26) & 077) {
- case 050: /* SB */
- case 051: /* SH */
- case 052: /* SWL */
- case 053: /* SW */
- case 054: /* SDL */
- case 055: /* SDR */
- case 056: /* SWR */
- case 070: /* SC */
- case 071: /* SWC1 */
- case 074: /* SCD */
- case 075: /* SDC1 */
- case 077: /* SD */
-#if !defined(__mips_isa_rev) || __mips_isa_rev < 6
- case 072: /* SWC2 */
- case 076: /* SDC2 */
-#endif
- is_write = 1;
- break;
- case 023: /* COP1X */
- /* Required in all versions of MIPS64 since
- MIPS64r1 and subsequent versions of MIPS32r2. */
- switch (insn & 077) {
- case 010: /* SWXC1 */
- case 011: /* SDXC1 */
- case 015: /* SUXC1 */
- is_write = 1;
- }
- break;
- }
-
- return handle_cpu_signal(pc, info, is_write, &uc->uc_sigmask);
-}
-
-#elif defined(__riscv)
-
-int cpu_signal_handler(int host_signum, void *pinfo,
- void *puc)
-{
- siginfo_t *info = pinfo;
- ucontext_t *uc = puc;
- greg_t pc = uc->uc_mcontext.__gregs[REG_PC];
- uint32_t insn = *(uint32_t *)pc;
- int is_write = 0;
-
- /* Detect store by reading the instruction at the program
- counter. Note: we currently only generate 32-bit
- instructions so we thus only detect 32-bit stores */
- switch (((insn >> 0) & 0b11)) {
- case 3:
- switch (((insn >> 2) & 0b11111)) {
- case 8:
- switch (((insn >> 12) & 0b111)) {
- case 0: /* sb */
- case 1: /* sh */
- case 2: /* sw */
- case 3: /* sd */
- case 4: /* sq */
- is_write = 1;
- break;
- default:
- break;
- }
- break;
- case 9:
- switch (((insn >> 12) & 0b111)) {
- case 2: /* fsw */
- case 3: /* fsd */
- case 4: /* fsq */
- is_write = 1;
- break;
- default:
- break;
- }
- break;
- default:
- break;
- }
- }
-
- /* Check for compressed instructions */
- switch (((insn >> 13) & 0b111)) {
- case 7:
- switch (insn & 0b11) {
- case 0: /*c.sd */
- case 2: /* c.sdsp */
- is_write = 1;
- break;
- default:
- break;
- }
- break;
- case 6:
- switch (insn & 0b11) {
- case 0: /* c.sw */
- case 3: /* c.swsp */
- is_write = 1;
- break;
- default:
- break;
- }
- break;
- default:
- break;
- }
-
- return handle_cpu_signal(pc, info, is_write, &uc->uc_sigmask);
-}
-
-#else
-
-#error host CPU specific signal handler needed
-
-#endif
-
/* The softmmu versions of these helpers are in cputlb.c. */
uint32_t cpu_ldub_data(CPUArchState *env, abi_ptr ptr)
diff --git a/linux-user/signal.c b/linux-user/signal.c
index 73c0f9066b..509dad7850 100644
--- a/linux-user/signal.c
+++ b/linux-user/signal.c
@@ -24,6 +24,7 @@
#include "qemu.h"
#include "trace.h"
#include "signal-common.h"
+#include "host-signal.h"
static struct target_sigaction sigact_table[TARGET_NSIG];
@@ -753,59 +754,85 @@ static inline void rewind_if_in_safe_syscall(void *puc)
}
#endif
-static void host_signal_handler(int host_signum, siginfo_t *info,
- void *puc)
+static void host_signal_handler(int host_sig, siginfo_t *info, void *puc)
{
CPUArchState *env = thread_cpu->env_ptr;
CPUState *cpu = env_cpu(env);
TaskState *ts = cpu->opaque;
-
- int sig;
+ bool sync_sig = false;
target_siginfo_t tinfo;
ucontext_t *uc = puc;
struct emulated_sigtable *k;
+ uintptr_t pc = 0;
+ int guest_sig;
- /* the CPU emulator uses some host signals to detect exceptions,
- we forward to it some signals */
- if ((host_signum == SIGSEGV || host_signum == SIGBUS)
- && info->si_code > 0) {
- if (cpu_signal_handler(host_signum, info, puc))
+ /*
+ * Non-spoofed SIGSEGV and SIGBUS are synchronous, and need special
+ * handling wrt signal blocking and unwinding. SIGSEGV may need to
+ * remove write-protection and restart the instruction.
+ */
+ if ((host_sig == SIGSEGV || host_sig == SIGBUS) && info->si_code > 0) {
+ pc = adjust_signal_pc(host_signal_pc(uc));
+ if (host_sig == SIGSEGV &&
+ info->si_code == SEGV_ACCERR &&
+ host_sigsegv_write(info, uc) &&
+ handle_sigsegv_accerr_write(cpu, &uc->uc_sigmask, pc,
+ (uintptr_t)info->si_addr)) {
return;
+ }
+ sync_sig = true;
+ } else {
+ rewind_if_in_safe_syscall(puc);
+
+ /*
+ * Block host signals until target signal handler entered.
+ * We can't block SIGSEGV or SIGBUS while we're executing
+ * guest code in case the guest code provokes one in the
+ * window between now and it getting out to the main loop.
+ * Signals will be unblocked again in process_pending_signals().
+ *
+ * WARNING: we cannot use sigfillset() here because the uc_sigmask
+ * field is a kernel sigset_t, which is much smaller than the
+ * libc sigset_t which sigfillset() operates on. Using sigfillset()
+ * would write 0xff bytes off the end of the structure and trash
+ * data on the struct.
+ * We can't use sizeof(uc->uc_sigmask) either, because the libc
+ * headers define the struct field with the wrong (too large) type.
+ */
+ memset(&uc->uc_sigmask, 0xff, SIGSET_T_SIZE);
+ sigdelset(&uc->uc_sigmask, SIGSEGV);
+ sigdelset(&uc->uc_sigmask, SIGBUS);
}
/* get target signal number */
- sig = host_to_target_signal(host_signum);
- if (sig < 1 || sig > TARGET_NSIG)
+ guest_sig = host_to_target_signal(host_sig);
+ if (guest_sig < 1 || guest_sig > TARGET_NSIG) {
return;
- trace_user_host_signal(env, host_signum, sig);
-
- rewind_if_in_safe_syscall(puc);
+ }
+ trace_user_host_signal(env, host_sig, guest_sig);
host_to_target_siginfo_noswap(&tinfo, info);
- k = &ts->sigtab[sig - 1];
+ k = &ts->sigtab[guest_sig - 1];
k->info = tinfo;
- k->pending = sig;
+ k->pending = guest_sig;
ts->signal_pending = 1;
- /* Block host signals until target signal handler entered. We
- * can't block SIGSEGV or SIGBUS while we're executing guest
- * code in case the guest code provokes one in the window between
- * now and it getting out to the main loop. Signals will be
- * unblocked again in process_pending_signals().
- *
- * WARNING: we cannot use sigfillset() here because the uc_sigmask
- * field is a kernel sigset_t, which is much smaller than the
- * libc sigset_t which sigfillset() operates on. Using sigfillset()
- * would write 0xff bytes off the end of the structure and trash
- * data on the struct.
- * We can't use sizeof(uc->uc_sigmask) either, because the libc
- * headers define the struct field with the wrong (too large) type.
+ /*
+ * For synchronous signals, unwind the cpu state to the faulting
+ * insn and then exit back to the main loop so that the signal
+ * is delivered immediately.
*/
- memset(&uc->uc_sigmask, 0xff, SIGSET_T_SIZE);
- sigdelset(&uc->uc_sigmask, SIGSEGV);
- sigdelset(&uc->uc_sigmask, SIGBUS);
+ if (sync_sig) {
+ clear_helper_retaddr();
+ sigprocmask(SIG_SETMASK, &uc->uc_sigmask, NULL);
+ cpu->exception_index = EXCP_INTERRUPT;
+ cpu_loop_exit_restore(cpu, pc);
+ }
- /* interrupt the virtual CPU as soon as possible */
+ /*
+ * Interrupt the virtual CPU as soon as possible, but for now
+ * return to continue with the current TB.
+ */
cpu_exit(thread_cpu);
}
--
2.25.1
- Re: [RFC PATCH 6/7] linux-user: Handle SIGSEGV/SIGBUS in host_to_target_siginfo_noswap, (continued)
- [RFC PATCH 2/7] accel/tcg: Split out adjust_signal_pc, Richard Henderson, 2021/09/13
- [RFC PATCH 3/7] accel/tcg: Split out handle_sigsegv_accerr_write, Richard Henderson, 2021/09/13
- [RFC PATCH 1/7] include/exec: Move cpu_signal_handler declaration, Richard Henderson, 2021/09/13
- [RFC PATCH 4/7] accel/tcg: Move clear_helper_retaddr to cpu loop, Richard Henderson, 2021/09/13
- [RFC PATCH 5/7] accel/tcg: Fold cpu_exit_tb_from_sighandler into caller, Richard Henderson, 2021/09/13
- [RFC PATCH 7/7] linux-user: Reorg cpu_signal_handler,
Richard Henderson <=
- Re: [RFC PATCH 0/7] linux-user: Streamline handling of SIGSEGV/SIGBUS, Richard Henderson, 2021/09/13