swh:1:snp:77163734605b0ec556b01d897b7bb4a7e30d46b6
Revision 96dc89d526ef77604376f06220e3d2931a0bfd58 authored by Michael Neuling on 25 September 2018, 09:36:47 UTC, committed by Michael Ellerman on 25 September 2018, 12:51:32 UTC
Current we store the userspace r1 to PACATMSCRATCH before finally saving it to the thread struct. In theory an exception could be taken here (like a machine check or SLB miss) that could write PACATMSCRATCH and hence corrupt the userspace r1. The SLB fault currently doesn't touch PACATMSCRATCH, but others do. We've never actually seen this happen but it's theoretically possible. Either way, the code is fragile as it is. This patch saves r1 to the kernel stack (which can't fault) before we turn MSR[RI] back on. PACATMSCRATCH is still used but only with MSR[RI] off. We then copy r1 from the kernel stack to the thread struct once we have MSR[RI] back on. Suggested-by: Breno Leitao <leitao@debian.org> Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
1 parent cf13435
Tip revision: a4412fdd49dc011bcc2c0d81ac4cab7457092650 authored by Steven Rostedt (Google) on 21 November 2022, 15:44:03 UTC
error-injection: Add prompt for function error injection
error-injection: Add prompt for function error injection
Tip revision: a4412fd
| File | Mode | Size |
|---|---|---|
| Documentation | ||
| LICENSES | ||
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| drivers | ||
| firmware | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | -rw-r--r-- | 12.8 KB |
| .cocciconfig | -rw-r--r-- | 59 bytes |
| .get_maintainer.ignore | -rw-r--r-- | 31 bytes |
| .gitattributes | -rw-r--r-- | 30 bytes |
| .gitignore | -rw-r--r-- | 1.5 KB |
| .mailmap | -rw-r--r-- | 9.7 KB |
| COPYING | -rw-r--r-- | 423 bytes |
| CREDITS | -rw-r--r-- | 96.4 KB |
| Kbuild | -rw-r--r-- | 2.2 KB |
| Kconfig | -rw-r--r-- | 563 bytes |
| MAINTAINERS | -rw-r--r-- | 458.5 KB |
| Makefile | -rw-r--r-- | 59.1 KB |
| README | -rw-r--r-- | 800 bytes |
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