This message generated a parse failure. Raw output follows here. Please use 'back' to navigate. From devnull@lkml.org Fri Apr 26 11:13:32 2024 Delivery-date: Thu, 02 Mar 2006 05:31:53 +0100 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751168AbWCBEb1 (ORCPT ); Wed, 1 Mar 2006 23:31:27 -0500 Received: from smtp.osdl.org ([65.172.181.4]:61921 "EHLO smtp.osdl.org") by vger.kernel.org with ESMTP id S1751163AbWCBEb0 convert rfc822-to-8bit (ORCPT ); Wed, 1 Mar 2006 23:31:26 -0500 Received: from shell0.pdx.osdl.net (fw.osdl.org [65.172.181.6]) by smtp.osdl.org (8.12.8/8.12.8) with ESMTP id k224MBDZ017499 (version=TLSv1/SSLv3 cipher=EDH-RSA-DES-CBC3-SHA bits=168 verify=NO); Wed, 1 Mar 2006 20:22:11 -0800 Received: from bix (shell0.pdx.osdl.net [10.9.0.31]) by shell0.pdx.osdl.net (8.13.1/8.11.6) with SMTP id k224MAEW005202; Wed, 1 Mar 2006 20:22:10 -0800 Date: Wed, 1 Mar 2006 20:20:58 -0800 From: Andrew Morton To: Paul Jackson Cc: pj@sgi.com, greg@kroah.com, ebiederm@xmission.com, linux-kernel@vger.kernel.org, yanmin.zhang@intel.com, Neil Brown Subject: Re: + proc-dont-lock-task_structs-indefinitely-cpuset-fix-2.patch added to -mm tree Message-Id: <20060301202058.42975408.akpm@osdl.org> In-Reply-To: <20060301154040.a7cb2afd.pj@sgi.com> References: <20060228183610.5253feb9.akpm@osdl.org> <20060228194525.0faebaaa.pj@sgi.com> <20060228201040.34a1e8f5.pj@sgi.com> <20060228212501.25464659.pj@sgi.com> <20060228234807.55f1b25f.pj@sgi.com> <20060301002631.48e3800 X-Mailer: Sylpheed version 1.0.4 (GTK+ 1.2.10; i386-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT X-Spam-Status: No, hits=-6 required=5 tests=PATCH_UNIFIED_DIFF_OSDL X-Spam-Checker-Version: SpamAssassin 2.63-osdl_revision__1.68__ X-MIMEDefang-Filter: osdl$Revision: 1.129 $ X-Scanned-By: MIMEDefang 2.36 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org Paul Jackson wrote: > > Andrew wrote: > > But Paul bisected it down to a particular not-merged patch, > > gregkh-driver-allow-sysfs-attribute-files-to-be-pollable.patch, which I'll > > admit doesn't look like it'll cause this. > > Verified. All very strange. afaict that patch is a no-op. The changelog claims that "This patch also uses sysfs_notify to allow /sys/block/md*/md/sync_action to be pollable", except that part is AWOL. It'd be interesting to see if just the data structure expansion: --- gregkh-2.6.orig/fs/sysfs/file.c +++ gregkh-2.6/fs/sysfs/file.c @@ -6,6 +6,7 @@ #include #include #include +#include #include #include @@ -57,6 +58,7 @@ struct sysfs_buffer { struct sysfs_ops * ops; struct semaphore sem; int needs_read_fill; + int event; }; --- gregkh-2.6.orig/include/linux/kobject.h +++ gregkh-2.6/include/linux/kobject.h @@ -24,6 +24,7 @@ #include #include #include +#include #include #define KOBJ_NAME_LEN 20 @@ -56,6 +57,7 @@ struct kobject { struct kset * kset; struct kobj_type * ktype; struct dentry * dentry; + wait_queue_head_t poll; }; extern int kobject_set_name(struct kobject *, const char *, ...) --- gregkh-2.6.orig/include/linux/sysfs.h +++ gregkh-2.6/include/linux/sysfs.h @@ -74,6 +74,7 @@ struct sysfs_dirent { umode_t s_mode; struct dentry * s_dentry; struct iattr * s_iattr; + atomic_t s_event; }; #define SYSFS_ROOT 0x0001 is sufficient to break it. Somewhat OT, but why is that patch dinking around with the attribute's parent directory? Why not just poll the attribute's sysfs file directly? . Possibly because we want the poller to be woken when an attribute actually gets instantiated within the directory?? Dunno. And it's a bit sad that poll() on an unpollable attribute will just hang. One would expect poll() to come back with -EINVAL. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/