The patch titled um: fix abort has been removed from the -mm tree. Its filename was um-fix-abort.patch This patch was dropped because it was merged into mainline or a subsystem tree The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: um: fix abort From: Richard Weinberger <richard@xxxxxx> os_dump_core() uses abort() to terminate UML in case of an fatal error. glibc's abort() calls raise(SIGABRT) which makes use of tgkill(). tgkill() has no effect within UML's kernel threads because they are not pthreads. As fallback abort() executes an invalid instruction to terminate the process. Therefore UML gets killed by SIGSEGV and leaves a ugly log entry in the host's kernel ring buffer. To get rid of this we use our own abort routine. Signed-off-by: Richard Weinberger <richard@xxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- arch/um/os-Linux/util.c | 23 ++++++++++++++++++++++- 1 file changed, 22 insertions(+), 1 deletion(-) diff -puN arch/um/os-Linux/util.c~um-fix-abort arch/um/os-Linux/util.c --- a/arch/um/os-Linux/util.c~um-fix-abort +++ a/arch/um/os-Linux/util.c @@ -5,6 +5,7 @@ #include <stdio.h> #include <stdlib.h> +#include <unistd.h> #include <errno.h> #include <signal.h> #include <string.h> @@ -75,6 +76,26 @@ void setup_hostinfo(char *buf, int len) host.release, host.version, host.machine); } +/* + * We cannot use glibc's abort(). It makes use of tgkill() which + * has no effect within UML's kernel threads. + * After that glibc would execute an invalid instruction to kill + * the calling process and UML crashes with SIGSEGV. + */ +static inline void __attribute__ ((noreturn)) uml_abort(void) +{ + sigset_t sig; + + fflush(NULL); + + if (!sigemptyset(&sig) && !sigaddset(&sig, SIGABRT)) + sigprocmask(SIG_UNBLOCK, &sig, 0); + + for (;;) + if (kill(getpid(), SIGABRT) < 0) + exit(127); +} + void os_dump_core(void) { int pid; @@ -116,5 +137,5 @@ void os_dump_core(void) while ((pid = waitpid(-1, NULL, WNOHANG | __WALL)) > 0) os_kill_ptraced_process(pid, 0); - abort(); + uml_abort(); } _ Patches currently in -mm which might be from richard@xxxxxx are origin.patch linux-next.patch mm-mmu_gather-rework.patch powerpc-mmu_gather-rework.patch sparc-mmu_gather-rework.patch s390-mmu_gather-rework.patch arm-mmu_gather-rework.patch sh-mmu_gather-rework.patch ia64-mmu_gather-rework.patch um-mmu_gather-rework.patch mm-now-that-all-old-mmu_gather-code-is-gone-remove-the-storage.patch mm-powerpc-move-the-rcu-page-table-freeing-into-generic-code.patch mm-extended-batches-for-generic-mmu_gather.patch lockdep-mutex-provide-mutex_lock_nest_lock.patch mm-remove-i_mmap_lock-lockbreak.patch mm-convert-i_mmap_lock-to-a-mutex.patch mm-revert-page_lock_anon_vma-lock-annotation.patch mm-improve-page_lock_anon_vma-comment.patch mm-use-refcounts-for-page_lock_anon_vma.patch mm-convert-anon_vma-lock-to-a-mutex.patch mm-optimize-page_lock_anon_vma-fast-path.patch sh-remove-warning-and-warning_symbol-from-struct-stacktrace_ops.patch um-os_dump_core-cleanup.patch um-fix-uml_lib_path.patch um-remove-sighup-handler.patch lib-consolidate-debug_stack_usage-option.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html