diff options
author | dchagin <dchagin@FreeBSD.org> | 2009-04-19 13:48:42 +0000 |
---|---|---|
committer | dchagin <dchagin@FreeBSD.org> | 2009-04-19 13:48:42 +0000 |
commit | ada9604fd24dc29bff6c92bc0943439bc14011f2 (patch) | |
tree | 5498ad96bf52e436830d5b5c228df2151231f121 | |
parent | 367054e0a3090fef4c4aba77a5b893d9650e64ff (diff) | |
download | FreeBSD-src-ada9604fd24dc29bff6c92bc0943439bc14011f2.zip FreeBSD-src-ada9604fd24dc29bff6c92bc0943439bc14011f2.tar.gz |
Remove support for FUTEX_REQUEUE operation.
Glibc does not use this operation since 2.3.3 version (Jun 2004),
as it is racy and replaced by FUTEX_CMP_REQUEUE operation.
Glibc versions prior to 2.3.3 fall back to FUTEX_WAKE when
FUTEX_REQUEUE returned EINVAL.
Any application directly using FUTEX_REQUEUE without return
value checking are definitely broken.
Limit quantity of messages per process about unsupported
operation.
Approved by: kib (mentor)
MFC after: 1 month
-rw-r--r-- | sys/compat/linux/linux_emul.c | 1 | ||||
-rw-r--r-- | sys/compat/linux/linux_emul.h | 1 | ||||
-rw-r--r-- | sys/compat/linux/linux_futex.c | 31 |
3 files changed, 20 insertions, 13 deletions
diff --git a/sys/compat/linux/linux_emul.c b/sys/compat/linux/linux_emul.c index 1ca48a3..dc81553 100644 --- a/sys/compat/linux/linux_emul.c +++ b/sys/compat/linux/linux_emul.c @@ -86,6 +86,7 @@ linux_proc_init(struct thread *td, pid_t child, int flags) em = malloc(sizeof *em, M_LINUX, M_WAITOK | M_ZERO); em->pid = child; em->pdeath_signal = 0; + em->used_requeue = 0; em->robust_futexes = NULL; if (flags & LINUX_CLONE_THREAD) { /* handled later in the code */ diff --git a/sys/compat/linux/linux_emul.h b/sys/compat/linux/linux_emul.h index 2c1b3ca..8ce27d7 100644 --- a/sys/compat/linux/linux_emul.h +++ b/sys/compat/linux/linux_emul.h @@ -51,6 +51,7 @@ struct linux_emuldata { struct linux_emuldata_shared *shared; int pdeath_signal; /* parent death signal */ + int used_requeue; /* uses deprecated futex op */ struct linux_robust_list_head *robust_futexes; diff --git a/sys/compat/linux/linux_futex.c b/sys/compat/linux/linux_futex.c index e1d214f..84ec36a 100644 --- a/sys/compat/linux/linux_futex.c +++ b/sys/compat/linux/linux_futex.c @@ -114,6 +114,7 @@ linux_sys_futex(struct thread *td, struct linux_sys_futex_args *args) struct timeval tv = {0, 0}; struct futex *f2; int op_ret; + struct linux_emuldata *em; #ifdef DEBUG if (ldebug(sys_futex)) @@ -262,19 +263,6 @@ linux_sys_futex(struct thread *td, struct linux_sys_futex_args *args) FUTEX_SYSTEM_UNLOCK; break; - case LINUX_FUTEX_REQUEUE: - FUTEX_SYSTEM_LOCK; - - f = futex_get(args->uaddr, FUTEX_UNLOCKED); - newf = futex_get(args->uaddr2, FUTEX_UNLOCKED); - td->td_retval[0] = futex_wake(f, args->val, newf, - (int)(unsigned long)args->timeout); - futex_put(f); - futex_put(newf); - - FUTEX_SYSTEM_UNLOCK; - break; - case LINUX_FUTEX_WAKE_OP: FUTEX_SYSTEM_LOCK; #ifdef DEBUG @@ -342,6 +330,23 @@ linux_sys_futex(struct thread *td, struct linux_sys_futex_args *args) /* not yet implemented */ return (ENOSYS); + case LINUX_FUTEX_REQUEUE: + + /* + * Glibc does not use this operation since Jun 2004 (2.3.3), + * as it is racy and replaced by FUTEX_CMP_REQUEUE operation. + * Glibc versions prior to 2.3.3 fall back to FUTEX_WAKE when + * FUTEX_REQUEUE returned EINVAL. + */ + em = em_find(td->td_proc, EMUL_DONTLOCK); + if (em->used_requeue == 0) { + printf("linux(%s (%d)) sys_futex: " + "unsupported futex_requeue op\n", + td->td_proc->p_comm, td->td_proc->p_pid); + em->used_requeue = 1; + } + return (EINVAL); + default: printf("linux_sys_futex: unknown op %d\n", args->op); |