Re: [PATCH] USB: storage: add "no SYNCHRONIZE CACHE" quirk

2015-12-15 Thread Alan Stern
On Tue, 15 Dec 2015, Oliver Neukum wrote: > On Thu, 2015-12-03 at 13:36 -0500, Alan Stern wrote: > > This is an old problem, but it was never resolved and it still affects > > people (Bugzilla #89511). In short, there are USB-(S)ATA bridges that > > claim to be write-back but don't support the SY

Re: [PATCH] USB: storage: add "no SYNCHRONIZE CACHE" quirk

2015-12-15 Thread Oliver Neukum
On Thu, 2015-12-03 at 13:36 -0500, Alan Stern wrote: > This is an old problem, but it was never resolved and it still affects > people (Bugzilla #89511). In short, there are USB-(S)ATA bridges that > claim to be write-back but don't support the SYNCHRONIZE CACHE > command. > This causes errors w

Re: [PATCH] USB: storage: add "no SYNCHRONIZE CACHE" quirk

2015-12-03 Thread Alan Stern
This is an old problem, but it was never resolved and it still affects people (Bugzilla #89511). In short, there are USB-(S)ATA bridges that claim to be write-back but don't support the SYNCHRONIZE CACHE command. This causes errors when filesystems try to flush data out to the disk. On Mon, 22

Re: [PATCH] USB: storage: add "no SYNCHRONIZE CACHE" quirk

2015-07-24 Thread Alan Stern
On Mon, 22 Jun 2015, James Bottomley wrote: > On Mon, 2015-06-22 at 13:48 -0400, Alan Stern wrote: > > On Mon, 22 Jun 2015, James Bottomley wrote: > > > > > On Mon, 2015-06-22 at 13:30 -0400, Alan Stern wrote: > > > > On Mon, 22 Jun 2015, James Bottomley wrote: > > > > > > > > > I'm not sure I e

Re: [PATCH] USB: storage: add "no SYNCHRONIZE CACHE" quirk

2015-06-26 Thread Stefan Richter
On Jun 26 James Bottomley wrote: > On Fri, 2015-06-26 at 11:43 +0200, Stefan Richter wrote: > > On Jun 22 James Bottomley wrote: [...] > > > Perhaps it might be wise to do this to every USB device ... for external > > > devices, the small performance gain doesn't really make up for the > > > potent

Re: [PATCH] USB: storage: add "no SYNCHRONIZE CACHE" quirk

2015-06-26 Thread James Bottomley
On Fri, 2015-06-26 at 11:43 +0200, Stefan Richter wrote: > On Jun 22 James Bottomley wrote: > > On Mon, 2015-06-22 at 13:30 -0400, Alan Stern wrote: > > > On Mon, 22 Jun 2015, James Bottomley wrote: > > > > Obviously, for a disk with a writeback cache that can't do flush, that > > > > window is muc

Re: [PATCH] USB: storage: add "no SYNCHRONIZE CACHE" quirk

2015-06-26 Thread Stefan Richter
On Jun 22 James Bottomley wrote: > On Mon, 2015-06-22 at 13:30 -0400, Alan Stern wrote: > > On Mon, 22 Jun 2015, James Bottomley wrote: > > > Obviously, for a disk with a writeback cache that can't do flush, that > > > window is much wider and the real solution should be to try to switch > > > the

RE: [PATCH] USB: storage: add "no SYNCHRONIZE CACHE" quirk

2015-06-23 Thread David Laight
From: Of James Bottomley > Sent: 22 June 2015 18:36 > To: Alan Stern ... > > > Obviously, for a disk with a writeback cache that can't do flush, that > > > window is much wider and the real solution should be to try to switch > > > the cache to write through. > > > > I agree. Doing the switch manu

Re: [PATCH] USB: storage: add "no SYNCHRONIZE CACHE" quirk

2015-06-22 Thread Markus Rathgeb
> Please test it now. I'd like to know if it fixes your problem, > regardless of how the discussion goes. Seems to be working, I also attached the kernel log. The "flush failed" will grow with disc activity (but that was to be expected). Jun 22 23:24:50 m3800 kernel: usb 1-3: new high-speed USB

Re: [PATCH] USB: storage: add "no SYNCHRONIZE CACHE" quirk

2015-06-22 Thread James Bottomley
On Mon, 2015-06-22 at 13:48 -0400, Alan Stern wrote: > On Mon, 22 Jun 2015, James Bottomley wrote: > > > On Mon, 2015-06-22 at 13:30 -0400, Alan Stern wrote: > > > On Mon, 22 Jun 2015, James Bottomley wrote: > > > > > > > I'm not sure I entirely like this: we are back again treating data > > > >

Re: [PATCH] USB: storage: add "no SYNCHRONIZE CACHE" quirk

2015-06-22 Thread Alan Stern
On Mon, 22 Jun 2015, Markus Rathgeb wrote: > >> > Maybe your patch will be acceptable, though. We'll have to hear from > >> > Markus and Matt. > >> > >> We'll probably have to take this to fsdevel as well ... they might have > >> opinions about whether the FS wants to be informed about flush fail

Re: [PATCH] USB: storage: add "no SYNCHRONIZE CACHE" quirk

2015-06-22 Thread Markus Rathgeb
>> > Maybe your patch will be acceptable, though. We'll have to hear from >> > Markus and Matt. >> >> We'll probably have to take this to fsdevel as well ... they might have >> opinions about whether the FS wants to be informed about flush failure. So, it is okay to wait for the end of that discu

Re: [PATCH] USB: storage: add "no SYNCHRONIZE CACHE" quirk

2015-06-22 Thread Alan Stern
On Mon, 22 Jun 2015, James Bottomley wrote: > On Mon, 2015-06-22 at 13:30 -0400, Alan Stern wrote: > > On Mon, 22 Jun 2015, James Bottomley wrote: > > > > > I'm not sure I entirely like this: we are back again treating data > > > corruption problems silently. > > > > > > However, I also believe

Re: [PATCH] USB: storage: add "no SYNCHRONIZE CACHE" quirk

2015-06-22 Thread James Bottomley
On Mon, 2015-06-22 at 13:30 -0400, Alan Stern wrote: > On Mon, 22 Jun 2015, James Bottomley wrote: > > > I'm not sure I entirely like this: we are back again treating data > > corruption problems silently. > > > > However, I also believe treating a single flush failure as a critical > > filesyst

Re: [PATCH] USB: storage: add "no SYNCHRONIZE CACHE" quirk

2015-06-22 Thread Alan Stern
On Mon, 22 Jun 2015, James Bottomley wrote: > I'm not sure I entirely like this: we are back again treating data > corruption problems silently. > > However, I also believe treating a single flush failure as a critical > filesystem error is also wrong: The data's all there correctly; all it > d

Re: [PATCH] USB: storage: add "no SYNCHRONIZE CACHE" quirk

2015-06-22 Thread James Bottomley
On Mon, 2015-06-22 at 10:55 -0400, Alan Stern wrote: > Some USB mass-storage devices claim to have a write-back cache but > don't support the SYNCHRONIZE CACHE command, which means there is no > way to tell these devices to flush their caches out to permanent > storage. Unfortunately, there is not