Note: This is a public test instance of Red Hat Bugzilla. The data contained within is a snapshot of the live data so any changes you make will not be reflected in the production Bugzilla. Email is disabled so feel free to test any aspect of the site that you want. File any problems you find or give feedback at bugzilla.redhat.com.
Bug 1258223
Summary: | [i686] BUG: unable to handle kernel paging request at ... in add_nops | ||
---|---|---|---|
Product: | [Fedora] Fedora | Reporter: | Richard W.M. Jones <rjones> |
Component: | kernel | Assignee: | Kernel Maintainer List <kernel-maint> |
Status: | CLOSED RAWHIDE | QA Contact: | Fedora Extras Quality Assurance <extras-qa> |
Severity: | unspecified | Docs Contact: | |
Priority: | unspecified | ||
Version: | rawhide | CC: | cebbert.lkml, gansalmon, itamar, jonathan, kernel-maint, madhu.chinakonda, mchehab |
Target Milestone: | --- | ||
Target Release: | --- | ||
Hardware: | Unspecified | ||
OS: | Unspecified | ||
Whiteboard: | |||
Fixed In Version: | Doc Type: | Bug Fix | |
Doc Text: | Story Points: | --- | |
Clone Of: | Environment: | ||
Last Closed: | 2015-09-08 16:11:01 UTC | Type: | Bug |
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: | 910269 |
Description
Richard W.M. Jones
2015-08-30 11:51:34 UTC
OK, I did reproduce it! It took a long time though. My set up is: 32 bit i686 Fedora Rawhide VM running on AMD hardware *Inside* this VM, I'm running: $ while libguestfs-test-tool >/tmp/log 2>&1; do echo -n .; done .................................................................................................................................................................................................................................................................................................................................................................................................................. and boom it fails after ~ 400 iterations with the same backtrace as above. I don't have any convenient 32 bit baremetal machine to test this on. 0: 8d 90 90 83 04 24 lea 0x24048390(%eax),%edx 6: 80 fc 0f cmp $0xf,%ah 9: a8 0f test $0xf,%al >> b: a0 06 1e 50 55 mov 0x55501e06,%al 10: 57 push %edi 11: 56 push %esi Interrupt 0x30 occurred while the alternatives code was replacing the initial 0x90,0x90,0x90 NOPs (from the ASM_CLAC macro) with the optimized version, 0x8d,0x76,0x00. Only the first byte has been replaced so far, and it makes a mess out of the insn decoding. Reported on lkml: http://marc.info/?l=linux-kernel&m=144098871818266&w=4 Seems to be a generally accepted solution upstream, which I have extensively tested and it works for me. https://marc.info/?l=linux-kernel&m=144127697521764&w=4 Added in Fedora git. It will be in the 4.3.0-0.rc0.git8.1 build (whenever that happens). Thanks for chasing this down everyone. |