lkml.org 
[lkml]   [2015]   [Jan]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRE: [PATCH 2/3] hv: vmbus_post_msg: retry the hypercall on HV_STATUS_INVALID_CONNECTION_ID
Date
> -----Original Message-----
> From: Jason Wang [mailto:jasowang@redhat.com]
> Sent: Friday, January 30, 2015 10:47 AM
> To: Dexuan Cui
> Cc: gregkh@linuxfoundation.org; linux-kernel@vger.kernel.org; driverdev-
> devel@linuxdriverproject.org; olaf@aepfle.de; apw@canonical.com; KY
> Srinivasan; Haiyang Zhang
> Subject: Re: [PATCH 2/3] hv: vmbus_post_msg: retry the hypercall on
> HV_STATUS_INVALID_CONNECTION_ID
>
>
>
> On Thu, Jan 29, 2015 at 7:02 PM, Dexuan Cui <decui@microsoft.com> wrote:
> > I got the hypercall error code on Hyper-V 2008 R2 when keeping running
> > "rmmod hv_netvsc; modprobe hv_netvsc; rmmod hv_utils; modprobe
> > hv_utils"
> > in a Linux guest.
> >
> > Without the patch, the driver can occasionally fail to load.
> >
> > CC: "K. Y. Srinivasan" <kys@microsoft.com>
> > Signed-off-by: Dexuan Cui <decui@microsoft.com>
> > ---
> > arch/x86/include/uapi/asm/hyperv.h | 1 +
> > drivers/hv/connection.c | 9 +++++++++
> > 2 files changed, 10 insertions(+)
> >
> > diff --git a/arch/x86/include/uapi/asm/hyperv.h
> > b/arch/x86/include/uapi/asm/hyperv.h
> > index 90c458e..b9daffb 100644
> > --- a/arch/x86/include/uapi/asm/hyperv.h
> > +++ b/arch/x86/include/uapi/asm/hyperv.h
> > @@ -225,6 +225,7 @@
> > #define HV_STATUS_INVALID_HYPERCALL_CODE 2
> > #define HV_STATUS_INVALID_HYPERCALL_INPUT 3
> > #define HV_STATUS_INVALID_ALIGNMENT 4
> > +#define HV_STATUS_INVALID_CONNECTION_ID 18
> > #define HV_STATUS_INSUFFICIENT_BUFFERS 19
> >
> > typedef struct _HV_REFERENCE_TSC_PAGE {
> > diff --git a/drivers/hv/connection.c b/drivers/hv/connection.c
> > index c4acd1c..8bd05f3 100644
> > --- a/drivers/hv/connection.c
> > +++ b/drivers/hv/connection.c
> > @@ -440,6 +440,15 @@ int vmbus_post_msg(void *buffer, size_t buflen)
> > ret = hv_post_message(conn_id, 1, buffer, buflen);
> >
> > switch (ret) {
> > + case HV_STATUS_INVALID_CONNECTION_ID:
> > + /*
> > + * We could get this if we send messages too
> > + * frequently or the host is under low resource
> > + * conditions: let's wait 1 more second before
> > + * retrying the hypercall.
> > + */
>
> The name HV_STATUS_INVALID_CONNECTION_ID is really confusing in this
> case. Since it does not show any meaning of lacking resources.
The description about the 'low host resource condition' might be not accurate.
I'll remove this part.

> > + msleep(1000);
> > + break;
> > case HV_STATUS_INSUFFICIENT_BUFFERS:
> > ret = -ENOMEM;
>
> I thought host should return this error value when lacking resources?
This should be correct.

> >
> > case -ENOMEM:
> > --

Thanks,
-- Dexuan
\
 
 \ /
  Last update: 2015-01-30 06:41    [W:0.103 / U:0.060 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site