The patch titled keys: don't need to use RCU in keyring_read() as semaphore is held has been removed from the -mm tree. Its filename was keys-dont-need-to-use-rcu-in-keyring_read-as-semaphore-is-held.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: keys: don't need to use RCU in keyring_read() as semaphore is held From: David Howells <dhowells@xxxxxxxxxx> keyring_read() doesn't need to use rcu_dereference() to access the keyring payload as the caller holds the key semaphore to prevent modifications from happening whilst the data is read out. This should solve the following warning: =================================================== [ INFO: suspicious rcu_dereference_check() usage. ] --------------------------------------------------- security/keys/keyring.c:204 invoked rcu_dereference_check() without protection! other info that might help us debug this: rcu_scheduler_active = 1, debug_locks = 0 1 lock held by keyctl/2144: #0: (&key->sem){+++++.}, at: [<ffffffff81177f7c>] keyctl_read_key+0x9c/0xcf stack backtrace: Pid: 2144, comm: keyctl Not tainted 2.6.34-rc2-cachefs #113 Call Trace: [<ffffffff8105121f>] lockdep_rcu_dereference+0xaa/0xb2 [<ffffffff811762d5>] keyring_read+0x4d/0xe7 [<ffffffff81177f8c>] keyctl_read_key+0xac/0xcf [<ffffffff811788d4>] sys_keyctl+0x75/0xb9 [<ffffffff81001eeb>] system_call_fastpath+0x16/0x1b Signed-off-by: David Howells <dhowells@xxxxxxxxxx> Cc: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- security/keys/keyring.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff -puN security/keys/keyring.c~keys-dont-need-to-use-rcu-in-keyring_read-as-semaphore-is-held security/keys/keyring.c --- a/security/keys/keyring.c~keys-dont-need-to-use-rcu-in-keyring_read-as-semaphore-is-held +++ a/security/keys/keyring.c @@ -199,7 +199,7 @@ static long keyring_read(const struct ke int loop, ret; ret = 0; - klist = rcu_dereference(keyring->payload.subscriptions); + klist = keyring->payload.subscriptions; if (klist) { /* calculate how much data we could return */ _ Patches currently in -mm which might be from dhowells@xxxxxxxxxx are origin.patch linux-next.patch fs-fscache-object-listc-fix-warning-on-32-bit.patch frv-extend-gdbstub-to-support-more-features-of-gdb.patch frv-extend-gdbstub-to-support-more-features-of-gdb-fix.patch frv-duplicate-output_buffer-of-e03.patch nommu-allow-private-mappings-of-read-only-devices.patch umh-creds-convert-call_usermodehelper_keys-to-use-subprocess_info-init.patch umh-creds-kill-subprocess_info-cred-logic.patch coredump-factor-out-the-not-ispipe-file-checks.patch coredump-cleanup-ispipe-code.patch coredump-factor-out-put_cred-calls.patch coredump-shift-down_writemmap_sem-into-coredump_wait.patch proc-get_nr_threads-doesnt-need-siglock-any-longer.patch proc_sched_show_task-use-get_nr_threads.patch keyctl_session_to_parent-use-thread_group_empty-to-check-singlethreadness.patch frv-use-asm-generic-scatterlisth.patch mn10300-use-asm-generic-scatterlisth.patch frv-remove-struct-file-argument-from-sysctl-proc_handler.patch mutex-subsystem-synchro-test-module.patch mutex-subsystem-synchro-test-module-add-missing-header-file.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