Bug 504623
Summary: | [RHEL5.4 Xen]: Save/restore between flipping and copying interface broken | ||
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Product: | Red Hat Enterprise Linux 5 | Reporter: | Chris Lalancette <clalance> |
Component: | kernel-xen | Assignee: | Xen Maintainance List <xen-maint> |
Status: | CLOSED WONTFIX | QA Contact: | Red Hat Kernel QE team <kernel-qe> |
Severity: | high | Docs Contact: | |
Priority: | high | ||
Version: | 5.4 | CC: | herbert.xu, pbonzini, xen-maint |
Target Milestone: | rc | ||
Target Release: | --- | ||
Hardware: | All | ||
OS: | Linux | ||
Whiteboard: | |||
Fixed In Version: | Doc Type: | Bug Fix | |
Doc Text: | Story Points: | --- | |
Clone Of: | 503139 | Environment: | |
Last Closed: | 2010-12-07 18:20:35 UTC | Type: | --- |
Regression: | --- | Mount Type: | --- |
Documentation: | --- | CRM: | |
Verified Versions: | Category: | --- | |
oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
Cloudforms Team: | --- | Target Upstream Version: | |
Embargoed: | |||
Bug Depends On: | |||
Bug Blocks: | 514490 |
Description
Chris Lalancette
2009-06-08 14:34:15 UTC
Just to further clarify; this issue was broken out of BZ 503139. During 5.4 development, we tried to make netback advertise only a copying interface; that is, we set "feature-rx-flip" to "0" in xenstore. The problem is that if you booted a guest where the feature-rx-flip wasn't set at all (like in a 5.3 dom0), then did a save, and then booted where "feature-rx-flip" was set to 0, netfront passes bogus frames to the hypervisor for the grant_table operations. This means that when dom0 receives a packet to deliver to the guest, netback goes to get a grant frame to put the data in and fails, so all networking to the guest fails. The purpose of this bug is to track down why netfront passes these bogus frames, and fix that. Once we have that fix in place, netfront can advertise "hey, I'm not buggy!" (as herbert suggests), and then netback can properly choose between copying and flipping. Chris Lalancette We now prefer a copying interface in the guest. This achieves the same effect (though only for 5.6 and 4.9 guests), but without affecting save/restore because guests that choose flipping will still do so when resuming. So, closing. |