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Date: Wed, 21 Dec 2016 09:38:32 +0800
From: Fam Zheng <famz@redhat.com>
Message-ID: <20161221013832.GD2994@lemon>
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Subject: Re: [Qemu-devel] [PATCH 0/4] RFC: A VFIO based block driver for
 NVMe device
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To: qemu-devel@nongnu.org
Cc: kwolf@redhat.com, qemu-block@nongnu.org, mreitz@redhat.com, borntraeger@de.ibm.com, stefanha@redhat.com, pbonzini@redhat.com, krister@redhat.com

On Tue, 12/20 15:04, no-reply@patchew.org wrote:
> ERROR: that open brace { should be on the previous line
> #287: FILE: util/vfio-helpers.c:214:
> +    struct vfio_group_status group_status =
> +    { .argsz = sizeof(group_status) };

Hmm, it may indeed look better.

> ERROR: Use of volatile is usually wrong: see Documentation/volatile-considered-harmful.txt
> #145: FILE: block/nvme.c:92:
> +    volatile uint32_t *doorbell;
> 
> ERROR: Use of volatile is usually wrong: see Documentation/volatile-considered-harmful.txt
> #169: FILE: block/nvme.c:116:
> +typedef volatile struct {

These are shared with hardware, even volatile-considered-harmful.txt admits it
can be valid:

> - Pointers to data structures in coherent memory which might be modified
>   by I/O devices can, sometimes, legitimately be volatile.  A ring buffer
>   used by a network adapter, where that adapter changes pointers to
>   indicate which descriptors have been processed, is an example of this
>   type of situation.

Fam