>From f1ef9167ca4494a8c6d71d0031c73e9c8841eadd
Fedora broke PTRACE_SYSEMU again, and UML crashes as a result when it
doesn't need to. This patch makes the PTRACE_SYSEMU check fail gracefully
and makes UML fall back to PTRACE_SYSCALL.
Signed-off-by: Jeff Dike <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
---
arch/um/os-Linux/start_up.c | 25 ++++++++++++++++---------
1 files changed, 16 insertions(+), 9 deletions(-)
diff --git a/arch/um/os-Linux/start_up.c b/arch/um/os-Linux/start_up.c
index b616e15..fd71bdb 100644
--- a/arch/um/os-Linux/start_up.c
+++ b/arch/um/os-Linux/start_up.c
@@ -122,8 +122,10 @@ static int stop_ptraced_child(int pid, int exitcode, int mustexit)
{
int status, n, ret = 0;
- if (ptrace(PTRACE_CONT, pid, 0, 0) < 0)
- fatal_perror("stop_ptraced_child : ptrace failed");
+ if (ptrace(PTRACE_CONT, pid, 0, 0) < 0) {
+ perror("stop_ptraced_child : ptrace failed");
+ return -1;
+ }
CATCH_EINTR(n = waitpid(pid, &status, 0));
if (!WIFEXITED(status) || (WEXITSTATUS(status) != exitcode)) {
int exit_with = WEXITSTATUS(status);
@@ -203,7 +205,7 @@ static void __init check_sysemu(void)
if (n < 0)
fatal_perror("check_sysemu : wait failed");
if (!WIFSTOPPED(status) || (WSTOPSIG(status) != SIGTRAP))
- fatal("check_sysemu : expected SIGTRAP, got status = %d",
+ fatal("check_sysemu : expected SIGTRAP, got status = %d\n",
status);
if (ptrace(PTRACE_GETREGS, pid, 0, regs) < 0)
@@ -245,9 +247,11 @@ static void __init check_sysemu(void)
if (WIFSTOPPED(status) &&
(WSTOPSIG(status) == (SIGTRAP|0x80))) {
- if (!count)
- fatal("check_ptrace : SYSEMU_SINGLESTEP "
- "doesn't singlestep");
+ if (!count) {
+ non_fatal("check_ptrace : SYSEMU_SINGLESTEP "
+ "doesn't singlestep");
+ goto fail;
+ }
n = ptrace(PTRACE_POKEUSR, pid, PT_SYSCALL_RET_OFFSET,
os_getpid());
if (n < 0)
@@ -257,9 +261,12 @@ static void __init check_sysemu(void)
}
else if (WIFSTOPPED(status) && (WSTOPSIG(status) == SIGTRAP))
count++;
- else
- fatal("check_ptrace : expected SIGTRAP or "
- "(SIGTRAP | 0x80), got status = %d", status);
+ else {
+ non_fatal("check_ptrace : expected SIGTRAP or "
+ "(SIGTRAP | 0x80), got status = %d\n",
+ status);
+ goto fail;
+ }
}
if (stop_ptraced_child(pid, 0, 0) < 0)
goto fail_stopped;
--
1.5.5.1
This is a note to let you know that we have just queued up the patch titled
Subject: uml: work around broken host PTRACE_SYSEMU
to the 2.6.25-stable tree. Its filename is
uml-work-around-broken-host-ptrace_sysemu.patch
A git repo of this tree can be found at
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
>From [email protected] Tue Aug 5 13:14:58 2008
From: Jeff Dike <[email protected]>
Date: Tue, 5 Aug 2008 16:14:09 -0400
Subject: uml: work around broken host PTRACE_SYSEMU
To: [email protected]
Cc: LKML <[email protected]>, uml-devel <[email protected]>
Message-ID: <[email protected]>
Content-Disposition: inline
From: Jeff Dike <[email protected]>
commit f1ef9167ca4494a8c6d71d0031c73e9c8841eadd upstream
Fedora broke PTRACE_SYSEMU again, and UML crashes as a result when it
doesn't need to. This patch makes the PTRACE_SYSEMU check fail gracefully
and makes UML fall back to PTRACE_SYSCALL.
Signed-off-by: Jeff Dike <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
arch/um/os-Linux/start_up.c | 25 ++++++++++++++++---------
1 file changed, 16 insertions(+), 9 deletions(-)
--- a/arch/um/os-Linux/start_up.c
+++ b/arch/um/os-Linux/start_up.c
@@ -122,8 +122,10 @@ static int stop_ptraced_child(int pid, i
{
int status, n, ret = 0;
- if (ptrace(PTRACE_CONT, pid, 0, 0) < 0)
- fatal_perror("stop_ptraced_child : ptrace failed");
+ if (ptrace(PTRACE_CONT, pid, 0, 0) < 0) {
+ perror("stop_ptraced_child : ptrace failed");
+ return -1;
+ }
CATCH_EINTR(n = waitpid(pid, &status, 0));
if (!WIFEXITED(status) || (WEXITSTATUS(status) != exitcode)) {
int exit_with = WEXITSTATUS(status);
@@ -203,7 +205,7 @@ static void __init check_sysemu(void)
if (n < 0)
fatal_perror("check_sysemu : wait failed");
if (!WIFSTOPPED(status) || (WSTOPSIG(status) != SIGTRAP))
- fatal("check_sysemu : expected SIGTRAP, got status = %d",
+ fatal("check_sysemu : expected SIGTRAP, got status = %d\n",
status);
if (ptrace(PTRACE_GETREGS, pid, 0, regs) < 0)
@@ -245,9 +247,11 @@ static void __init check_sysemu(void)
if (WIFSTOPPED(status) &&
(WSTOPSIG(status) == (SIGTRAP|0x80))) {
- if (!count)
- fatal("check_ptrace : SYSEMU_SINGLESTEP "
- "doesn't singlestep");
+ if (!count) {
+ non_fatal("check_ptrace : SYSEMU_SINGLESTEP "
+ "doesn't singlestep");
+ goto fail;
+ }
n = ptrace(PTRACE_POKEUSR, pid, PT_SYSCALL_RET_OFFSET,
os_getpid());
if (n < 0)
@@ -257,9 +261,12 @@ static void __init check_sysemu(void)
}
else if (WIFSTOPPED(status) && (WSTOPSIG(status) == SIGTRAP))
count++;
- else
- fatal("check_ptrace : expected SIGTRAP or "
- "(SIGTRAP | 0x80), got status = %d", status);
+ else {
+ non_fatal("check_ptrace : expected SIGTRAP or "
+ "(SIGTRAP | 0x80), got status = %d\n",
+ status);
+ goto fail;
+ }
}
if (stop_ptraced_child(pid, 0, 0) < 0)
goto fail_stopped;
Patches currently in stable-queue which might be from [email protected] are
queue-2.6.25/uml-fix-build-when-slob-is-enabled.patch
queue-2.6.25/uml-fix-bad-ntp-interaction-with-clock.patch
queue-2.6.25/uml-physical-memory-shouldn-t-include-initial-stack.patch
queue-2.6.25/uml-track-and-make-up-lost-ticks.patch
queue-2.6.25/uml-missed-kmalloc-in-pcap_user.c.patch
queue-2.6.25/uml-deal-with-host-time-going-backwards.patch
queue-2.6.25/uml-deal-with-inaccessible-address-space-start.patch
queue-2.6.25/uml-missing-export-of-csum_partial-on-uml-amd64.patch
queue-2.6.25/uml-memcpy-export-needs-to-follow-host-declaration.patch
queue-2.6.25/uml-stub-needs-to-tolerate-sigwinch.patch
queue-2.6.25/uml-work-around-broken-host-ptrace_sysemu.patch
queue-2.6.25/uml-fix-gcc-ices-and-unresolved-externs.patch
queue-2.6.25/uml-fix-boot-crash.patch