* [PATCH 1/2] linux-user/s390x: signal with SIGFPE on compare-and-trap
2021-06-21 14:14 [PATCH 0/2] linux-user/s390x: signal with SIGFPE on compare-and-trap Jonathan Albrecht
@ 2021-06-21 14:14 ` Jonathan Albrecht
2021-06-23 2:27 ` Ilya Leoshkevich
2021-06-21 14:14 ` [PATCH 2/2] tests/tcg: Test that compare-and-trap raises SIGFPE Jonathan Albrecht
` (2 subsequent siblings)
3 siblings, 1 reply; 7+ messages in thread
From: Jonathan Albrecht @ 2021-06-21 14:14 UTC (permalink / raw)
To: qemu-devel
Cc: Jonathan Albrecht, iii, david, cohuck, richard.henderson, laurent,
borntraeger, qemu-s390x, krebbel
Currently when a compare-and-trap instruction is executed, qemu will
always raise a SIGILL signal. On real hardware, a SIGFPE is raised.
Change the PGM_DATA case in cpu_loop to follow the behavior in
linux kernel /arch/s390/kernel/traps.c.
* Only raise SIGILL if DXC == 0
* If DXC matches an IEEE exception, raise SIGFPE with correct si_code
* Raise SIGFPE with si_code == 0 for everything else
When applied on 20210602002210.3144559-2-iii@linux.ibm.com, this fixes
crashes in the java jdk such as the linked bug.
Buglink: https://bugs.launchpad.net/qemu/+bug/1920913
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/319
Signed-off-by: Jonathan Albrecht <jonathan.albrecht@linux.vnet.ibm.com>
---
linux-user/s390x/cpu_loop.c | 19 ++++++++++---------
1 file changed, 10 insertions(+), 9 deletions(-)
diff --git a/linux-user/s390x/cpu_loop.c b/linux-user/s390x/cpu_loop.c
index 72ba9170ed..def5c046f7 100644
--- a/linux-user/s390x/cpu_loop.c
+++ b/linux-user/s390x/cpu_loop.c
@@ -117,11 +117,13 @@ void cpu_loop(CPUS390XState *env)
case PGM_DATA:
n = (env->fpc >> 8) & 0xff;
- if (n == 0xff) {
- /* compare-and-trap */
+ if (n == 0) {
goto do_sigill_opn;
- } else {
- /* An IEEE exception, simulated or otherwise. */
+ }
+
+ sig = TARGET_SIGFPE;
+ if ((n & 0x03) == 0) {
+ /* An IEEE exception, simulated or otherwise. */
if (n & 0x80) {
n = TARGET_FPE_FLTINV;
} else if (n & 0x40) {
@@ -132,13 +134,12 @@ void cpu_loop(CPUS390XState *env)
n = TARGET_FPE_FLTUND;
} else if (n & 0x08) {
n = TARGET_FPE_FLTRES;
- } else {
- /* ??? Quantum exception; BFP, DFP error. */
- goto do_sigill_opn;
}
- sig = TARGET_SIGFPE;
- goto do_signal_pc;
+ } else {
+ /* compare-and-trap */
+ n = 0;
}
+ goto do_signal_pc;
default:
fprintf(stderr, "Unhandled program exception: %#x\n", n);
--
2.31.1
^ permalink raw reply related [flat|nested] 7+ messages in thread* [PATCH 2/2] tests/tcg: Test that compare-and-trap raises SIGFPE
2021-06-21 14:14 [PATCH 0/2] linux-user/s390x: signal with SIGFPE on compare-and-trap Jonathan Albrecht
2021-06-21 14:14 ` [PATCH 1/2] " Jonathan Albrecht
@ 2021-06-21 14:14 ` Jonathan Albrecht
2021-06-21 14:24 ` [PATCH 0/2] linux-user/s390x: signal with SIGFPE on compare-and-trap no-reply
2021-07-05 9:29 ` Cornelia Huck
3 siblings, 0 replies; 7+ messages in thread
From: Jonathan Albrecht @ 2021-06-21 14:14 UTC (permalink / raw)
To: qemu-devel
Cc: Jonathan Albrecht, iii, david, cohuck, richard.henderson, laurent,
borntraeger, qemu-s390x, krebbel
Signed-off-by: Jonathan Albrecht <jonathan.albrecht@linux.vnet.ibm.com>
---
tests/tcg/s390x/Makefile.target | 1 +
tests/tcg/s390x/trap.c | 100 ++++++++++++++++++++++++++++++++
2 files changed, 101 insertions(+)
create mode 100644 tests/tcg/s390x/trap.c
diff --git a/tests/tcg/s390x/Makefile.target b/tests/tcg/s390x/Makefile.target
index cdb7d85316..4bd6db6679 100644
--- a/tests/tcg/s390x/Makefile.target
+++ b/tests/tcg/s390x/Makefile.target
@@ -9,3 +9,4 @@ TESTS+=pack
TESTS+=mvo
TESTS+=mvc
TESTS+=signal
+TESTS+=trap
diff --git a/tests/tcg/s390x/trap.c b/tests/tcg/s390x/trap.c
new file mode 100644
index 0000000000..d48ad070d4
--- /dev/null
+++ b/tests/tcg/s390x/trap.c
@@ -0,0 +1,100 @@
+/*
+ * Copyright 2021 IBM Corp.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or (at
+ * your option) any later version. See the COPYING file in the top-level
+ * directory.
+ */
+
+#include <stdarg.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <errno.h>
+#include <string.h>
+#include <signal.h>
+
+static void error1(const char *filename, int line, const char *fmt, ...)
+{
+ va_list ap;
+ va_start(ap, fmt);
+ fprintf(stderr, "%s:%d: ", filename, line);
+ vfprintf(stderr, fmt, ap);
+ fprintf(stderr, "\n");
+ va_end(ap);
+ exit(1);
+}
+
+static int __chk_error(const char *filename, int line, int ret)
+{
+ if (ret < 0) {
+ error1(filename, line, "%m (ret=%d, errno=%d/%s)",
+ ret, errno, strerror(errno));
+ }
+ return ret;
+}
+
+#define error(fmt, ...) error1(__FILE__, __LINE__, fmt, ## __VA_ARGS__)
+
+#define chk_error(ret) __chk_error(__FILE__, __LINE__, (ret))
+
+int sigfpe_count = 0;
+int sigill_count = 0;
+
+static void sig_handler(int sig, siginfo_t *si, void *puc)
+{
+ if (sig == SIGFPE) {
+ if (si->si_code != 0) {
+ error("unexpected si_code: 0x%x != 0", si->si_code);
+ }
+ ++sigfpe_count;
+ return;
+ }
+
+ if (sig == SIGILL) {
+ ++sigill_count;
+ return;
+ }
+
+ error("unexpected signal 0x%x\n", sig);
+}
+
+int main(int argc, char **argv)
+{
+ struct sigaction act;
+
+ /* Set up SIG handler */
+ act.sa_sigaction = sig_handler;
+ sigemptyset(&act.sa_mask);
+ act.sa_flags = SA_SIGINFO;
+ chk_error(sigaction(SIGFPE, &act, NULL));
+ chk_error(sigaction(SIGILL, &act, NULL));
+
+ uint64_t z = 0x0ull;
+ uint64_t lz = 0xffffffffffffffffull;
+ asm volatile (
+ "lg %%r13,%[lz]\n"
+ "cgitne %%r13,0\n" /* SIGFPE */
+ "lg %%r13,%[z]\n"
+ "cgitne %%r13,0\n" /* no trap */
+ "nopr\n"
+ "lg %%r13,%[lz]\n"
+ "citne %%r13,0\n" /* SIGFPE */
+ "lg %%r13,%[z]\n"
+ "citne %%r13,0\n" /* no trap */
+ "nopr\n"
+ :
+ : [z] "m" (z), [lz] "m" (lz)
+ : "memory", "r13");
+
+ if (sigfpe_count != 2) {
+ error("unexpected SIGFPE count: %d != 2", sigfpe_count);
+ }
+ if (sigill_count != 0) {
+ error("unexpected SIGILL count: %d != 0", sigill_count);
+ }
+
+ printf("PASS\n");
+ return 0;
+}
--
2.31.1
^ permalink raw reply related [flat|nested] 7+ messages in thread* Re: [PATCH 0/2] linux-user/s390x: signal with SIGFPE on compare-and-trap
2021-06-21 14:14 [PATCH 0/2] linux-user/s390x: signal with SIGFPE on compare-and-trap Jonathan Albrecht
2021-06-21 14:14 ` [PATCH 1/2] " Jonathan Albrecht
2021-06-21 14:14 ` [PATCH 2/2] tests/tcg: Test that compare-and-trap raises SIGFPE Jonathan Albrecht
@ 2021-06-21 14:24 ` no-reply
2021-07-05 9:29 ` Cornelia Huck
3 siblings, 0 replies; 7+ messages in thread
From: no-reply @ 2021-06-21 14:24 UTC (permalink / raw)
To: jonathan.albrecht
Cc: jonathan.albrecht, iii, david, cohuck, richard.henderson,
qemu-devel, laurent, borntraeger, qemu-s390x, krebbel
Patchew URL: https://patchew.org/QEMU/20210621141452.2045-1-jonathan.albrecht@linux.vnet.ibm.com/
Hi,
This series seems to have some coding style problems. See output below for
more information:
Type: series
Message-id: 20210621141452.2045-1-jonathan.albrecht@linux.vnet.ibm.com
Subject: [PATCH 0/2] linux-user/s390x: signal with SIGFPE on compare-and-trap
=== TEST SCRIPT BEGIN ===
#!/bin/bash
git rev-parse base > /dev/null || exit 0
git config --local diff.renamelimit 0
git config --local diff.renames True
git config --local diff.algorithm histogram
./scripts/checkpatch.pl --mailback base..
=== TEST SCRIPT END ===
Updating 3c8cf5a9c21ff8782164d1def7f44bd888713384
From https://github.com/patchew-project/qemu
- [tag update] patchew/20210526142438.281477-1-f4bug@amsat.org -> patchew/20210526142438.281477-1-f4bug@amsat.org
- [tag update] patchew/20210614083800.1166166-1-richard.henderson@linaro.org -> patchew/20210614083800.1166166-1-richard.henderson@linaro.org
* [new tag] patchew/20210621141452.2045-1-jonathan.albrecht@linux.vnet.ibm.com -> patchew/20210621141452.2045-1-jonathan.albrecht@linux.vnet.ibm.com
Switched to a new branch 'test'
c6b3ba6 tests/tcg: Test that compare-and-trap raises SIGFPE
7bab442 linux-user/s390x: signal with SIGFPE on compare-and-trap
=== OUTPUT BEGIN ===
1/2 Checking commit 7bab4427a5e9 (linux-user/s390x: signal with SIGFPE on compare-and-trap)
2/2 Checking commit c6b3ba625805 (tests/tcg: Test that compare-and-trap raises SIGFPE)
WARNING: added, moved or deleted file(s), does MAINTAINERS need updating?
#25:
new file mode 100644
ERROR: do not initialise globals to 0 or NULL
#71: FILE: tests/tcg/s390x/trap.c:42:
+int sigfpe_count = 0;
ERROR: do not initialise globals to 0 or NULL
#72: FILE: tests/tcg/s390x/trap.c:43:
+int sigill_count = 0;
ERROR: trailing whitespace
#83: FILE: tests/tcg/s390x/trap.c:54:
+ $
ERROR: trailing whitespace
#116: FILE: tests/tcg/s390x/trap.c:87:
+ : $
total: 4 errors, 1 warnings, 104 lines checked
Patch 2/2 has style problems, please review. If any of these errors
are false positives report them to the maintainer, see
CHECKPATCH in MAINTAINERS.
=== OUTPUT END ===
Test command exited with code: 1
The full log is available at
http://patchew.org/logs/20210621141452.2045-1-jonathan.albrecht@linux.vnet.ibm.com/testing.checkpatch/?type=message.
---
Email generated automatically by Patchew [https://patchew.org/].
Please send your feedback to patchew-devel@redhat.com
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH 0/2] linux-user/s390x: signal with SIGFPE on compare-and-trap
2021-06-21 14:14 [PATCH 0/2] linux-user/s390x: signal with SIGFPE on compare-and-trap Jonathan Albrecht
` (2 preceding siblings ...)
2021-06-21 14:24 ` [PATCH 0/2] linux-user/s390x: signal with SIGFPE on compare-and-trap no-reply
@ 2021-07-05 9:29 ` Cornelia Huck
2021-07-06 18:47 ` jonathan.albrecht
3 siblings, 1 reply; 7+ messages in thread
From: Cornelia Huck @ 2021-07-05 9:29 UTC (permalink / raw)
To: Jonathan Albrecht, qemu-devel
Cc: Jonathan Albrecht, iii, david, richard.henderson, laurent,
borntraeger, qemu-s390x, krebbel
On Mon, Jun 21 2021, Jonathan Albrecht <jonathan.albrecht@linux.vnet.ibm.com> wrote:
> qemu-s390x signals with SIGILL on compare-and-trap instructions. This
> breaks OpenJDK which expects SIGFPE in its implementation of implicit
> exceptions.
>
> This patch depends on [PATCH v3 0/2] target/s390x: Fix SIGILL psw.addr
> reporting.
> https://lore.kernel.org/qemu-devel/20210602002210.3144559-1-iii@linux.ibm.com/
>
> Based-on: 20210602002210.3144559-1-iii@linux.ibm.com
>
> Jonathan Albrecht (2):
> linux-user/s390x: signal with SIGFPE on compare-and-trap
> tests/tcg: Test that compare-and-trap raises SIGFPE
>
> linux-user/s390x/cpu_loop.c | 19 +++---
> tests/tcg/s390x/Makefile.target | 1 +
> tests/tcg/s390x/trap.c | 100 ++++++++++++++++++++++++++++++++
> 3 files changed, 111 insertions(+), 9 deletions(-)
> create mode 100644 tests/tcg/s390x/trap.c
Assuming that this will also go through the linux-user tree:
Acked-by: Cornelia Huck <cohuck@redhat.com>
^ permalink raw reply [flat|nested] 7+ messages in thread