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Date:   Tue, 28 May 2019 15:18:23 +0200
From:   Lars Ellenberg <lars.ellenberg@linbit.com>
To:     Eric Wheeler <drbd-dev@lists.ewheeler.net>
Cc:     drbd-dev@lists.linbit.com, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] drbd: fix discard_zeroes_if_aligned regression
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On Fri, May 10, 2019 at 05:36:32PM +0000, Eric Wheeler wrote:
> Hi Lars,
> 
> We just tried 4.19.x and this bugs still exists. We applied the patch 
> which was originally submitted to this thread and it still applies cleanly 
> and seems to work for our use case. You mentioned that you had some older 
> code which zeroed out unaligned discard requests (or perhaps it was for a 
> different purpose) that you may be able to use to patch this. Could you 
> dig those up and see if we can get this solved?
> 
> It would be nice to be able to use drbd with thin backing volumes from the 
> vanilla kernel. If this has already been fixed in something newer than 
> 4.19, then please point me to the commit.

I think it was merged upstream in 5.0
f31e583aa2c2 drbd: introduce P_ZEROES (REQ_OP_WRITE_ZEROES on the "wire")

-- 
: Lars Ellenberg
: LINBIT | Keeping the Digital World Running
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