Bug 1560494
| Summary: | i686: Using invpcid_flush_all_nonglobals() can cause user-space panic on .i686 | ||
|---|---|---|---|
| Product: | Red Hat Enterprise Linux 6 | Reporter: | Vratislav Bendel <vbendel> |
| Component: | kernel | Assignee: | Waiman Long <llong> |
| kernel sub component: | Memory Management | QA Contact: | Li Wang <liwan> |
| Status: | CLOSED ERRATA | Docs Contact: | |
| Severity: | high | ||
| Priority: | high | CC: | lwang, mkostyukevic, nyelle, stalexan, vbendel, xiawu |
| Version: | 6.9 | Keywords: | Regression |
| Target Milestone: | rc | ||
| Target Release: | --- | ||
| Hardware: | Unspecified | ||
| OS: | Unspecified | ||
| Whiteboard: | |||
| Fixed In Version: | kernel-2.6.32-754.el6 | Doc Type: | If docs needed, set a value |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2018-06-19 05:05:17 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: | |||
Patch(es) committed on kernel repository and kernel is undergoing testing Patch(es) available on kernel-2.6.32-754.el6 Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. For information on the advisory, and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. https://access.redhat.com/errata/RHSA-2018:1854 |
Description of problem: Customer's java application can cause panic, apparently after the CPU performs invpcid flush. Customer bisected this to the following commit: commit c6f35cdfc82ca083c041a24fdf33e1b84f80912d [x86] mm/kaiser: use invpcid to flush the two kaiser PCID AISD From what I understand, then apparently the following might be the problem (however I don't currently understand why): static inline void __native_flush_tlb(void) { - __load_cr3(native_read_cr3()); + if (!static_cpu_has(X86_FEATURE_INVPCID)) { + __load_cr3(native_read_cr3()); + return; + } + /* + * Note, this works with CR4.PCIDE=0 or 1. + */ + invpcid_flush_all_nonglobals(); } Other modifications done by the commit are either under #CONFIG_KAISER or #CONFIG_X86_64, which are not included into .i686 build. Additionally, disabling invpcid on boot-cmd-line *seems to resolve* the problem. (using 'noinvpcid' boot parameter) Version-Release number of selected component (if applicable): kernel-2.6.32-696.18.7.el6.i686 How reproducible: Always Steps to Reproduce: TBA Actual results: 0xf error_code page_fault panic Expected results: no panic Additional info: Usage of 'noinvpcid' boot-param in -696.18.7 version is exclusive to #CONFIG_X86_64, however on upstream it's general. Customer has tested the workaround ('noinvpcid') on -696.18.7.test kernel, simply modified to enable it on .i686.