Public bug reported:
>From my testing it seems that QEMU built against musl libc crashes on
pthread_cancel cancel calls - if the binary is also built with musl
libc.
Minimal sample:
#include <pthread.h>
#include <stdio.h>
#include <unistd.h>
void* threadfunc(void* ignored) {
while (1) {
pause();
}
return NULL;
}
int main() {
pthread_t thread;
pthread_create(&thread, NULL, &threadfunc, NULL);
sleep(1);
pthread_cancel(thread);
printf("OK, alive\n");
}
In an Alpine Linux aarch64 chroot (on an x86_64 host) the binary will
just output RT33 and has exit code 161.
Using qemu-aarch64 on an x86_64 host results in the output (fish shell)
fish: “qemu-aarch64-static ./musl-stat…” terminated by signal Unknown
(Unknown)
or (bash)
Real-time signal 2
and exit code 164.
It doesn't matter whether the binary is linked dynamically or static.
You can see my test results in the following table:
| | QEMU glibc | QEMU musl |
|----------------------|------------|-----------|
| binary glibc dynamic | ✓ | ✓ |
| binary glibc static | ✓ | ✓ |
| binary musl dynamic | ✓ | ✗ |
| binary musl static | ✓ | ✗ |
Both QEMU builds are v5.1.0 (glibc v2.32 / musl v1.2.1)
I've uploaded all my compile and test commands (plus a script to
conveniently run them all) to https://github.com/z3ntu/qemu-
pthread_cancel . It also includes the built binaries if needed. The test
script output can be found at https://github.com/z3ntu/qemu-
pthread_cancel/blob/master/results.txt
Further links:
- https://gitlab.com/postmarketOS/pmaports/-/issues/190#note_141902075
- https://gitlab.com/postmarketOS/pmbootstrap/-/issues/1970
** Affects: qemu
Importance: Undecided
Status: New
--
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https://bugs.launchpad.net/bugs/1895305
Title:
pthread_cancel fails with "RT33" with musl libc
Status in QEMU:
New
Bug description:
From my testing it seems that QEMU built against musl libc crashes on
pthread_cancel cancel calls - if the binary is also built with musl
libc.
Minimal sample:
#include <pthread.h>
#include <stdio.h>
#include <unistd.h>
void* threadfunc(void* ignored) {
while (1) {
pause();
}
return NULL;
}
int main() {
pthread_t thread;
pthread_create(&thread, NULL, &threadfunc, NULL);
sleep(1);
pthread_cancel(thread);
printf("OK, alive\n");
}
In an Alpine Linux aarch64 chroot (on an x86_64 host) the binary will
just output RT33 and has exit code 161.
Using qemu-aarch64 on an x86_64 host results in the output (fish shell)
fish: “qemu-aarch64-static ./musl-stat…” terminated by signal Unknown
(Unknown)
or (bash)
Real-time signal 2
and exit code 164.
It doesn't matter whether the binary is linked dynamically or static.
You can see my test results in the following table:
| | QEMU glibc | QEMU musl |
|----------------------|------------|-----------|
| binary glibc dynamic | ✓ | ✓ |
| binary glibc static | ✓ | ✓ |
| binary musl dynamic | ✓ | ✗ |
| binary musl static | ✓ | ✗ |
Both QEMU builds are v5.1.0 (glibc v2.32 / musl v1.2.1)
I've uploaded all my compile and test commands (plus a script to
conveniently run them all) to https://github.com/z3ntu/qemu-
pthread_cancel . It also includes the built binaries if needed. The
test script output can be found at https://github.com/z3ntu/qemu-
pthread_cancel/blob/master/results.txt
Further links:
- https://gitlab.com/postmarketOS/pmaports/-/issues/190#note_141902075
- https://gitlab.com/postmarketOS/pmbootstrap/-/issues/1970
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