The patch titled Subject: idr: remove WARN_ON_ONCE() on negative IDs has been added to the -mm tree. Its filename is idr-remove-warn_on_once-on-negative-ids.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Tejun Heo <tj@xxxxxxxxxx> Subject: idr: remove WARN_ON_ONCE() on negative IDs idr_find(), idr_remove() and idr_replace() used to silently ignore the sign bit and perform lookup with the rest of the bits. The weird behavior has been changed such that negative IDs are treated as invalid. As the behavior change was subtle, WARN_ON_ONCE() was added in the hope of determining who's calling idr functions with negative IDs so that they can be examined for problems. Up until now, all two reported cases are ID number coming directly from userland and getting fed into idr_find() and the warnings seem to cause more problems than being helpful. Drop the WARN_ON_ONCE()s. Signed-off-by: Tejun Heo <tj@xxxxxxxxxx> Reported-by: <markus@xxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- lib/idr.c | 16 +++------------- 1 file changed, 3 insertions(+), 13 deletions(-) diff -puN lib/idr.c~idr-remove-warn_on_once-on-negative-ids lib/idr.c --- a/lib/idr.c~idr-remove-warn_on_once-on-negative-ids +++ a/lib/idr.c @@ -569,8 +569,7 @@ void idr_remove(struct idr *idp, int id) struct idr_layer *p; struct idr_layer *to_free; - /* see comment in idr_find_slowpath() */ - if (WARN_ON_ONCE(id < 0)) + if (id < 0) return; sub_remove(idp, (idp->layers - 1) * IDR_BITS, id); @@ -667,15 +666,7 @@ void *idr_find_slowpath(struct idr *idp, int n; struct idr_layer *p; - /* - * If @id is negative, idr_find() used to ignore the sign bit and - * performed lookup with the rest of bits, which is weird and can - * lead to very obscure bugs. We're now returning NULL for all - * negative IDs but just in case somebody was depending on the sign - * bit being ignored, let's trigger WARN_ON_ONCE() so that they can - * be detected and fixed. WARN_ON_ONCE() can later be removed. - */ - if (WARN_ON_ONCE(id < 0)) + if (id < 0) return NULL; p = rcu_dereference_raw(idp->top); @@ -824,8 +815,7 @@ void *idr_replace(struct idr *idp, void int n; struct idr_layer *p, *old_p; - /* see comment in idr_find_slowpath() */ - if (WARN_ON_ONCE(id < 0)) + if (id < 0) return ERR_PTR(-EINVAL); p = idp->top; _ Patches currently in -mm which might be from tj@xxxxxxxxxx are origin.patch linux-next.patch idr-remove-warn_on_once-on-negative-ids.patch block-restore-proc-partitions-to-not-display-non-partitionable-removable-devices.patch rtc-add-devm_rtc_device_registerunregister.patch coredump-only-sigkill-should-interrupt-the-coredumping-task.patch coredump-ensure-that-sigkill-always-kills-the-dumping-thread.patch coredump-sanitize-the-setting-of-signal-group_exit_code.patch coredump-factor-out-the-setting-of-pf_dumpcore.patch freezer-do-not-send-a-fake-signal-to-a-pf_dumpcore-thread.patch coredump-make-wait_for_dump_helpers-freezable.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