glibc complained with "The futex facility returned an unexpected error
code.". It turned out that the futex syscall returned -ERESTARTSYS because
a signal is pending. arch_do_signal_or_restart() restored the syscall
parameters (nameley regs->gprs[2]) and set PIF_SYSCALL_RESTART. When
another signal is made pending later in the exit loop
arch_do_signal_or_restart() is called again. This function clears
PIF_SYSCALL_RESTART and checks the return code which is set in
regs->gprs[2]. However, regs->gprs[2] was restored in the previous run
and no longer contains -ERESTARTSYS, so PIF_SYSCALL_RESTART isn't set
again and the syscall is skipped.
Fix this by not clearing PIF_SYSCALL_RESTART - it is already cleared in
__do_syscall() when the syscall is restarted.
Reported-by: Bjoern Walk <bwalk@linux.ibm.com>
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Fixes:
|
||
|---|---|---|
| Documentation | ||
| LICENSES | ||
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
README
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.