From: Paolo Bonzini <pbonzini@redhat.com>
To: Jiahuan Zhang <jiahuanzhang90@gmail.com>
Cc: QEMU Developers <qemu-devel@nongnu.org>,
Peter Maydell <peter.maydell@linaro.org>
Subject: Re: [Qemu-devel] Guest application reading from pl011 without device driver
Date: Thu, 23 Mar 2017 18:31:41 +0100 [thread overview]
Message-ID: <d355d12a-9f37-b7ca-aab0-1fcd0d481a8f@redhat.com> (raw)
In-Reply-To: <CAJy91CYfOUZ+_TrN6-tLtWuPX-3_gRc7bfNa4anW0iM42i1FTg@mail.gmail.com>
On 23/03/2017 18:28, Jiahuan Zhang wrote:
> Hi, the method doesn't work for pipe. It still causes the same issue.
> The only difference is that the first byte in the UART fifo can be read
> by the guest app.
> So now my guest app can immediately read 17bytes when the host is
> sending data continuously,
> then guest app is unable to read.
>
> Now there is a solution-to-be. Set the qemu pipe chardev to wait for 1
> millisecond before do a next ReadFile(),
> then the pl011 can deliver the complete large data by the 16-byte fifo
> continuously to the guest app.
>
> Is it rational? Or is this host -CPU-dependent?
Post the patch, maybe you have a bug.
Paolo
next prev parent reply other threads:[~2017-03-23 17:31 UTC|newest]
Thread overview: 26+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-03-21 16:32 [Qemu-devel] Guest application reading from pl011 without device driver Jiahuan Zhang
2017-03-21 16:39 ` Peter Maydell
2017-03-21 16:47 ` Jiahuan Zhang
2017-03-21 16:50 ` Peter Maydell
2017-03-21 16:59 ` Jiahuan Zhang
2017-03-21 17:10 ` Jiahuan Zhang
2017-03-21 17:16 ` Peter Maydell
2017-03-21 17:48 ` Jiahuan Zhang
2017-03-21 17:55 ` Peter Maydell
[not found] ` <CAJy91CZ4Ed-HGHLkzEc1dqQbo32d-eTE1S1ovO_ZwkDdTpkQXQ@mail.gmail.com>
[not found] ` <CAJy91CaCV40FgSP55qWZeZgkQ=2+E8Cr7xdbu9pn5HLEo+6JJQ@mail.gmail.com>
2017-03-21 18:11 ` Jiahuan Zhang
2017-03-21 18:28 ` Peter Maydell
2017-03-21 18:33 ` Jiahuan Zhang
2017-03-22 8:40 ` Paolo Bonzini
2017-03-22 8:48 ` Jiahuan Zhang
2017-03-22 9:37 ` Paolo Bonzini
2017-03-22 10:28 ` Jiahuan Zhang
2017-03-22 11:27 ` Paolo Bonzini
2017-03-23 10:12 ` Jiahuan Zhang
2017-03-23 10:35 ` Paolo Bonzini
2017-03-23 17:28 ` Jiahuan Zhang
2017-03-23 17:31 ` Paolo Bonzini [this message]
2017-03-24 7:24 ` Jiahuan Zhang
2017-03-24 10:00 ` Jiahuan Zhang
2017-05-01 12:06 ` Jiahuan Zhang
2017-03-22 11:07 ` Peter Maydell
2017-03-22 11:33 ` Paolo Bonzini
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