From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:51400) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bzfZW-00010C-Nd for qemu-devel@nongnu.org; Thu, 27 Oct 2016 03:57:59 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bzfZR-0007qF-TX for qemu-devel@nongnu.org; Thu, 27 Oct 2016 03:57:58 -0400 References: <1477539023-16503-1-git-send-email-aik@ozlabs.ru> From: Paolo Bonzini Message-ID: <0f42682c-2595-36ce-baa7-e874324cbe4f@redhat.com> Date: Thu, 27 Oct 2016 09:57:47 +0200 MIME-Version: 1.0 In-Reply-To: <1477539023-16503-1-git-send-email-aik@ozlabs.ru> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] "block: use aio_bh_schedule_oneshot" breaks ibm-vscsi List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Alexey Kardashevskiy , qemu-devel@nongnu.org Cc: qemu-ppc@nongnu.org, David Gibson , Kevin Wolf , Stefan Hajnoczi On 27/10/2016 05:30, Alexey Kardashevskiy wrote: > Hi, > > I just discovered that fffb6e12233002c26c0ee9ff92fa87927cd779f2 broke > ibm-vscsi, the guest booting stops (I waited for a minute) at: > > [ 0.809286] ibmvscsi 71000001: SRP_VERSION: 16.a > [ 0.809766] ibmvscsi 71000001: Maximum ID: 64 Maximum LUN: 32 Maximum Channel: 3 > [ 0.810059] scsi host0: IBM POWER Virtual SCSI Adapter 1.5.9 > [ 0.810634] ibmvscsi 71000001: partner initialization complete > [ 0.810999] ibmvscsi 71000001: host srp version: 16.a, host partition qemu (0), OS 2, max io 2097152 > [ 0.811507] ibmvscsi 71000001: sent SRP login > [ 0.811705] ibmvscsi 71000001: SRP_LOGIN succeeded > [ 0.824062] scsi 0:0:0:0: Direct-Access QEMU QEMU HARDDISK 2.5+ PQ: 0 ANSI: 5 > [ 1.018526] sd 0:0:0:0: Attached scsi generic sg0 type 0 > [ 1.019352] sd 0:0:0:0: [sda] 67108864 512-byte logical blocks: (34.4 GB/32.0 GiB) > [ 1.020274] sd 0:0:0:0: [sda] Write Protect is off > [ 1.020667] sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA > [ 1.023390] sda: sda1 sda2 sda3 > [ 1.025819] sd 0:0:0:0: [sda] Attached SCSI disk > > > When I switch to virtio-vscsi, I get a bit further: > > Begin: Loading essential drivers ... done. > Begin: Running /scripts/init-premount ... done. > Begin: Mounting root file system ... Begin: Running /scripts/local-top ... done. > Begin: Running /scripts/local-premount ... done. > Begin: Will now check root file system ... fsck from util-linux 2.27.1 > [/sbin/fsck.ext4 (1) -- /dev/sda2] fsck.ext4 -a -C0 /dev/sda2 > fsck.ext4: Read-only file system while trying to open /dev/sda2 > Disk write-protected; use the -n option to do a read-only > check of the device. > fsck exited with status code 8 > done. > Warning: File system check failed but did not detect errors > > and then I get login prompt. > > > With reverted fffb6e12233002c26c0ee9ff92fa87927cd779f2, virtio-vscsi behaves > the same (so I assume fffb6e122 does not affect it) and ibm-vscsi behaves nicely: > > Begin: Loading essential drivers ... done. > Begin: Running /scripts/init-premount ... done. > Begin: Mounting root file system ... Begin: Running /scripts/local-top ... done. > Begin: Running /scripts/local-premount ... done. > Begin: Will now check root file system ... fsck from util-linux 2.27.1 > [/sbin/fsck.ext4 (1) -- /dev/sda2] fsck.ext4 -a -C0 /dev/sda2 > /dev/sda2: clean, 66846/2011296 files, 574929/8034048 blocks > done. > [ 0.996954] EXT4-fs (sda2): mounted filesystem with ordered data mode. Opts: (null) > done. > > and then I get login prompt. > > > fffb6e12233002c26c0ee9ff92fa87927cd779f2 is: > === > block: use aio_bh_schedule_oneshot > > This simplifies bottom half handlers by removing calls to qemu_bh_delete and > thus removing the need to stash the bottom half pointer in the opaque > datum. > === > > Any clues what is wrong? Thanks. Hi, it turns out that the fix is already included in the 20-patch series "dataplane: remove RFifoLock". It's in patch 17. diff --git a/async.c b/async.c index f30d011..fb37b03 100644 --- a/async.c +++ b/async.c @@ -61,6 +61,7 @@ void aio_bh_schedule_oneshot(AioContext *ctx, QEMUBHFunc *cb, void *opaque) smp_wmb(); ctx->first_bh = bh; qemu_mutex_unlock(&ctx->bh_lock); + aio_notify(ctx); } QEMUBH *aio_bh_new(AioContext *ctx, QEMUBHFunc *cb, void *opaque) Thanks, Paolo