From: Richard Henderson <richard.henderson@linaro.org>
To: qemu-devel@nongnu.org
Cc: laurent@vivier.eu
Subject: [PATCH v2 06/41] linux-user: Reorg handling for SIGSEGV
Date: Sat, 18 Sep 2021 11:44:52 -0700 [thread overview]
Message-ID: <20210918184527.408540-7-richard.henderson@linaro.org> (raw)
In-Reply-To: <20210918184527.408540-1-richard.henderson@linaro.org>
Add stub host-signal.h for all linux-user hosts.
Add new code replacing cpu_signal_handler.
Full migration will happen one host at a time.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
linux-user/host/aarch64/host-signal.h | 1 +
linux-user/host/arm/host-signal.h | 1 +
linux-user/host/i386/host-signal.h | 1 +
linux-user/host/mips/host-signal.h | 1 +
linux-user/host/ppc/host-signal.h | 1 +
linux-user/host/ppc64/host-signal.h | 1 +
linux-user/host/riscv/host-signal.h | 1 +
linux-user/host/s390/host-signal.h | 1 +
linux-user/host/s390x/host-signal.h | 1 +
linux-user/host/sparc/host-signal.h | 1 +
linux-user/host/sparc64/host-signal.h | 1 +
linux-user/host/x32/host-signal.h | 1 +
linux-user/host/x86_64/host-signal.h | 1 +
linux-user/signal.c | 109 ++++++++++++++++++++++----
14 files changed, 106 insertions(+), 16 deletions(-)
create mode 100644 linux-user/host/aarch64/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/riscv/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/x32/host-signal.h
create mode 100644 linux-user/host/x86_64/host-signal.h
diff --git a/linux-user/host/aarch64/host-signal.h b/linux-user/host/aarch64/host-signal.h
new file mode 100644
index 0000000000..f4b4d65031
--- /dev/null
+++ b/linux-user/host/aarch64/host-signal.h
@@ -0,0 +1 @@
+#define HOST_SIGNAL_PLACEHOLDER
diff --git a/linux-user/host/arm/host-signal.h b/linux-user/host/arm/host-signal.h
new file mode 100644
index 0000000000..f4b4d65031
--- /dev/null
+++ b/linux-user/host/arm/host-signal.h
@@ -0,0 +1 @@
+#define HOST_SIGNAL_PLACEHOLDER
diff --git a/linux-user/host/i386/host-signal.h b/linux-user/host/i386/host-signal.h
new file mode 100644
index 0000000000..f4b4d65031
--- /dev/null
+++ b/linux-user/host/i386/host-signal.h
@@ -0,0 +1 @@
+#define HOST_SIGNAL_PLACEHOLDER
diff --git a/linux-user/host/mips/host-signal.h b/linux-user/host/mips/host-signal.h
new file mode 100644
index 0000000000..f4b4d65031
--- /dev/null
+++ b/linux-user/host/mips/host-signal.h
@@ -0,0 +1 @@
+#define HOST_SIGNAL_PLACEHOLDER
diff --git a/linux-user/host/ppc/host-signal.h b/linux-user/host/ppc/host-signal.h
new file mode 100644
index 0000000000..f4b4d65031
--- /dev/null
+++ b/linux-user/host/ppc/host-signal.h
@@ -0,0 +1 @@
+#define HOST_SIGNAL_PLACEHOLDER
diff --git a/linux-user/host/ppc64/host-signal.h b/linux-user/host/ppc64/host-signal.h
new file mode 100644
index 0000000000..f4b4d65031
--- /dev/null
+++ b/linux-user/host/ppc64/host-signal.h
@@ -0,0 +1 @@
+#define HOST_SIGNAL_PLACEHOLDER
diff --git a/linux-user/host/riscv/host-signal.h b/linux-user/host/riscv/host-signal.h
new file mode 100644
index 0000000000..f4b4d65031
--- /dev/null
+++ b/linux-user/host/riscv/host-signal.h
@@ -0,0 +1 @@
+#define HOST_SIGNAL_PLACEHOLDER
diff --git a/linux-user/host/s390/host-signal.h b/linux-user/host/s390/host-signal.h
new file mode 100644
index 0000000000..f4b4d65031
--- /dev/null
+++ b/linux-user/host/s390/host-signal.h
@@ -0,0 +1 @@
+#define HOST_SIGNAL_PLACEHOLDER
diff --git a/linux-user/host/s390x/host-signal.h b/linux-user/host/s390x/host-signal.h
new file mode 100644
index 0000000000..f4b4d65031
--- /dev/null
+++ b/linux-user/host/s390x/host-signal.h
@@ -0,0 +1 @@
+#define HOST_SIGNAL_PLACEHOLDER
diff --git a/linux-user/host/sparc/host-signal.h b/linux-user/host/sparc/host-signal.h
new file mode 100644
index 0000000000..f4b4d65031
--- /dev/null
+++ b/linux-user/host/sparc/host-signal.h
@@ -0,0 +1 @@
+#define HOST_SIGNAL_PLACEHOLDER
diff --git a/linux-user/host/sparc64/host-signal.h b/linux-user/host/sparc64/host-signal.h
new file mode 100644
index 0000000000..f4b4d65031
--- /dev/null
+++ b/linux-user/host/sparc64/host-signal.h
@@ -0,0 +1 @@
+#define HOST_SIGNAL_PLACEHOLDER
diff --git a/linux-user/host/x32/host-signal.h b/linux-user/host/x32/host-signal.h
new file mode 100644
index 0000000000..f4b4d65031
--- /dev/null
+++ b/linux-user/host/x32/host-signal.h
@@ -0,0 +1 @@
+#define HOST_SIGNAL_PLACEHOLDER
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..f4b4d65031
--- /dev/null
+++ b/linux-user/host/x86_64/host-signal.h
@@ -0,0 +1 @@
+#define HOST_SIGNAL_PLACEHOLDER
diff --git a/linux-user/signal.c b/linux-user/signal.c
index 5ea8e4584a..6f953f10d4 100644
--- a/linux-user/signal.c
+++ b/linux-user/signal.c
@@ -18,12 +18,15 @@
*/
#include "qemu/osdep.h"
#include "qemu/bitops.h"
+#include "hw/core/tcg-cpu-ops.h"
+
#include <sys/ucontext.h>
#include <sys/resource.h>
#include "qemu.h"
#include "trace.h"
#include "signal-common.h"
+#include "host-signal.h"
static struct target_sigaction sigact_table[TARGET_NSIG];
@@ -761,41 +764,115 @@ 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;
target_siginfo_t tinfo;
ucontext_t *uc = puc;
struct emulated_sigtable *k;
+ int guest_sig;
+#ifdef HOST_SIGNAL_PLACEHOLDER
/* the CPU emulator uses some host signals to detect exceptions,
we forward to it some signals */
- if ((host_signum == SIGSEGV || host_signum == SIGBUS)
+ if ((host_sig == SIGSEGV || host_sig == SIGBUS)
&& info->si_code > 0) {
- if (cpu_signal_handler(host_signum, info, puc))
+ if (cpu_signal_handler(host_sig, info, puc))
return;
}
+#else
+ uintptr_t pc = 0;
+ bool sync_sig = false;
+
+ /*
+ * Non-spoofed SIGSEGV and SIGBUS are synchronous, and need special
+ * handling wrt signal blocking and unwinding.
+ */
+ if ((host_sig == SIGSEGV || host_sig == SIGBUS) && info->si_code > 0) {
+ MMUAccessType access_type;
+ uintptr_t host_addr;
+ abi_ptr guest_addr;
+ bool is_write;
+
+ host_addr = (uintptr_t)info->si_addr;
+
+ /*
+ * Convert forcefully to guest address space: addresses outside
+ * reserved_va are still valid to report via SEGV_MAPERR.
+ */
+ guest_addr = h2g_nocheck(host_addr);
+
+ pc = host_signal_pc(uc);
+ is_write = host_signal_write(info, uc);
+ access_type = adjust_signal_pc(&pc, is_write);
+
+ if (host_sig == SIGSEGV) {
+ const struct TCGCPUOps *tcg_ops;
+
+ if (info->si_code == SEGV_ACCERR && h2g_valid(host_addr)) {
+ /* If this was a write to a TB protected page, restart. */
+ if (is_write &&
+ handle_sigsegv_accerr_write(cpu, &uc->uc_sigmask,
+ pc, guest_addr)) {
+ return;
+ }
+
+ /*
+ * With reserved_va, the whole address space is PROT_NONE,
+ * which means that we may get ACCERR when we want MAPERR.
+ */
+ if (page_get_flags(guest_addr) & PAGE_VALID) {
+ /* maperr = false; */
+ } else {
+ info->si_code = SEGV_MAPERR;
+ }
+ }
+
+ sigprocmask(SIG_SETMASK, &uc->uc_sigmask, NULL);
+
+ tcg_ops = CPU_GET_CLASS(cpu)->tcg_ops;
+ tcg_ops->tlb_fill(cpu, guest_addr, 0, access_type,
+ MMU_USER_IDX, false, pc);
+ g_assert_not_reached();
+ } else {
+ sigprocmask(SIG_SETMASK, &uc->uc_sigmask, NULL);
+ }
+
+ sync_sig = true;
+ }
+#endif
/* 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);
+ }
+ trace_user_host_signal(env, host_sig, guest_sig);
+
+ host_to_target_siginfo_noswap(&tinfo, info);
+ k = &ts->sigtab[guest_sig - 1];
+ k->info = tinfo;
+ k->pending = guest_sig;
+ ts->signal_pending = 1;
+
+#ifndef HOST_SIGNAL_PLACEHOLDER
+ /*
+ * 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.
+ */
+ if (sync_sig) {
+ cpu->exception_index = EXCP_INTERRUPT;
+ cpu_loop_exit_restore(cpu, pc);
+ }
+#endif
rewind_if_in_safe_syscall(puc);
- host_to_target_siginfo_noswap(&tinfo, info);
- k = &ts->sigtab[sig - 1];
- k->info = tinfo;
- k->pending = sig;
- ts->signal_pending = 1;
-
- /* Block host signals until target signal handler entered. We
+ /*
+ * 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
--
2.25.1
next prev parent reply other threads:[~2021-09-18 18:57 UTC|newest]
Thread overview: 71+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-09-18 18:44 [PATCH v2 00/41] linux-user: Streamline handling of SIGSEGV Richard Henderson
2021-09-18 18:44 ` [PATCH v2 01/41] accel/tcg: Split out adjust_signal_pc Richard Henderson
2021-09-18 18:44 ` [PATCH v2 02/41] accel/tcg: Move clear_helper_retaddr to cpu loop Richard Henderson
2021-09-19 19:35 ` Warner Losh
2021-09-18 18:44 ` [PATCH v2 03/41] accel/tcg: Split out handle_sigsegv_accerr_write Richard Henderson
2021-09-18 18:44 ` [PATCH v2 04/41] accel/tcg: Fold cpu_exit_tb_from_sighandler into caller Richard Henderson
2021-09-18 18:44 ` [PATCH v2 05/41] configure: Merge riscv32 and riscv64 host architectures Richard Henderson
2021-09-19 17:56 ` Philippe Mathieu-Daudé
2021-09-19 22:57 ` Alistair Francis
2021-09-18 18:44 ` Richard Henderson [this message]
2021-09-19 18:02 ` [PATCH v2 06/41] linux-user: Reorg handling for SIGSEGV Philippe Mathieu-Daudé
2021-09-19 19:01 ` Warner Losh
2021-09-19 23:01 ` Alistair Francis
2021-09-18 18:44 ` [PATCH v2 07/41] linux-user/host/x86: Populate host_signal.h Richard Henderson
2021-09-18 18:44 ` [PATCH v2 08/41] linux-user/host/ppc: " Richard Henderson
2021-09-19 19:34 ` Warner Losh
2021-09-18 18:44 ` [PATCH v2 09/41] linux-user/host/alpha: " Richard Henderson
2021-09-19 18:03 ` Philippe Mathieu-Daudé
2021-09-19 18:07 ` Richard Henderson
2021-09-19 18:11 ` Philippe Mathieu-Daudé
2021-09-19 18:13 ` Philippe Mathieu-Daudé
2021-09-18 18:44 ` [PATCH v2 10/41] linux-user/host/sparc: " Richard Henderson
2021-09-18 18:44 ` [PATCH v2 11/41] linux-user/host/arm: " Richard Henderson
2021-09-18 18:44 ` [PATCH v2 12/41] linux-user/host/aarch64: " Richard Henderson
2021-09-18 18:44 ` [PATCH v2 13/41] linux-user/host/s390: " Richard Henderson
2021-09-19 18:07 ` Philippe Mathieu-Daudé
2021-09-18 18:45 ` [PATCH v2 14/41] linux-user/host/mips: " Richard Henderson
2021-09-19 18:08 ` Philippe Mathieu-Daudé
2021-09-18 18:45 ` [PATCH v2 15/41] linux-user/host/riscv: " Richard Henderson
2021-09-18 18:45 ` [PATCH v2 16/41] target/arm: Fixup comment re handle_cpu_signal Richard Henderson
2021-09-18 18:45 ` [PATCH v2 17/41] linux-user/host/riscv: Improve host_signal_write Richard Henderson
2021-09-18 18:45 ` [PATCH v2 18/41] linux-user/signal: Drop HOST_SIGNAL_PLACEHOLDER Richard Henderson
2021-09-19 18:18 ` Philippe Mathieu-Daudé
2021-09-19 18:59 ` Warner Losh
2021-09-18 18:45 ` [PATCH v2 19/41] hw/core: Add TCGCPUOps.record_sigsegv Richard Henderson
2021-09-19 18:22 ` Philippe Mathieu-Daudé
2021-09-19 18:24 ` Philippe Mathieu-Daudé
2021-09-19 18:32 ` Richard Henderson
2021-09-18 18:45 ` [PATCH v2 20/41] linux-user: Add raise_sigsegv Richard Henderson
2021-09-19 18:26 ` Philippe Mathieu-Daudé
2021-09-19 18:35 ` Richard Henderson
2021-09-19 18:43 ` Philippe Mathieu-Daudé
2021-09-19 18:53 ` Warner Losh
2021-09-18 18:45 ` [PATCH v2 21/41] target/alpha: Make alpha_cpu_tlb_fill sysemu only Richard Henderson
2021-09-18 18:45 ` [PATCH v2 22/41] target/arm: Use raise_sigsegv for mte tag lookup Richard Henderson
2021-09-18 18:45 ` [PATCH v2 23/41] target/arm: Implement arm_cpu_record_sigsegv Richard Henderson
2021-09-18 18:45 ` [PATCH v2 24/41] target/cris: Make cris_cpu_tlb_fill sysemu only Richard Henderson
2021-09-19 18:28 ` Philippe Mathieu-Daudé
2021-09-18 18:45 ` [PATCH v2 25/41] target/hexagon: Remove hexagon_cpu_tlb_fill Richard Henderson
2021-09-18 18:45 ` [PATCH v2 26/41] target/hppa: Make hppa_cpu_tlb_fill sysemu only Richard Henderson
2021-09-18 18:45 ` [PATCH v2 27/41] target/i386: Implement x86_cpu_record_sigsegv Richard Henderson
2021-09-19 18:32 ` Philippe Mathieu-Daudé
2021-09-19 18:59 ` Warner Losh
2021-09-18 18:45 ` [PATCH v2 28/41] target/m68k: Make m68k_cpu_tlb_fill sysemu only Richard Henderson
2021-09-18 18:45 ` [PATCH v2 29/41] target/microblaze: Make mb_cpu_tlb_fill " Richard Henderson
2021-09-18 18:45 ` [PATCH v2 30/41] target/mips: Make mips_cpu_tlb_fill " Richard Henderson
2021-09-18 18:45 ` [PATCH v2 31/41] target/nios2: Make nios2_cpu_tlb_fill " Richard Henderson
2021-09-18 18:45 ` [PATCH v2 32/41] linux-user/openrisc: Adjust signal for EXCP_RANGE, EXCP_FPE Richard Henderson
2021-09-18 18:45 ` [PATCH v2 33/41] target/openrisc: Make openrisc_cpu_tlb_fill sysemu only Richard Henderson
2021-09-18 18:45 ` [PATCH v2 34/41] target/ppc: Implement ppc_cpu_record_sigsegv Richard Henderson
2021-09-19 18:37 ` Philippe Mathieu-Daudé
2021-09-18 18:45 ` [PATCH v2 35/41] target/riscv: Make riscv_cpu_tlb_fill sysemu only Richard Henderson
2021-09-18 18:45 ` [PATCH v2 36/41] target/s390x: Use probe_access_flags in s390_probe_access Richard Henderson
2021-09-18 18:45 ` [PATCH v2 37/41] target/s390x: Implement s390_cpu_record_sigsegv Richard Henderson
2021-09-19 18:39 ` Philippe Mathieu-Daudé
2021-09-18 18:45 ` [PATCH v2 38/41] target/sh4: Make sh4_cpu_tlb_fill sysemu only Richard Henderson
2021-09-18 18:45 ` [PATCH v2 39/41] target/sparc: Make sparc_cpu_tlb_fill " Richard Henderson
2021-09-18 18:45 ` [PATCH v2 40/41] target/xtensa: Make xtensa_cpu_tlb_fill " Richard Henderson
2021-09-18 18:45 ` [PATCH v2 41/41] accel/tcg: Restrict TCGCPUOps::tlb_fill() to sysemu Richard Henderson
2021-09-19 18:40 ` Philippe Mathieu-Daudé
2021-09-19 10:38 ` [PATCH v2 00/41] linux-user: Streamline handling of SIGSEGV Philippe Mathieu-Daudé
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20210918184527.408540-7-richard.henderson@linaro.org \
--to=richard.henderson@linaro.org \
--cc=laurent@vivier.eu \
--cc=qemu-devel@nongnu.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.