forked from Minki/linux
7895470063
We have suffered recrusive frozen PE a lot, which was caused by IO accesses during the PE reset. Ben came up with the good idea to keep frozen PE until recovery (BAR restore) gets done. With that, IO accesses during PE reset are dropped by hardware and wouldn't incur the recrusive frozen PE any more. The patch implements the idea. We don't clear the frozen state until PE reset is done completely. During the period, the EEH core expects unfrozen state from backend to keep going. So we have to reuse EEH_PE_RESET flag, which has been set during PE reset, to return normal state from backend. The side effect is we have to clear frozen state for towice (PE reset and clear it explicitly), but that's harmless. We have some limitations on pHyp. pHyp doesn't allow to enable IO or DMA for unfrozen PE. So we don't enable them on unfrozen PE in eeh_pci_enable(). We have to enable IO before grabbing logs on pHyp. Otherwise, 0xFF's is always returned from PCI config space. Also, we had wrong return value from eeh_pci_enable() for EEH_OPT_THAW_DMA case. The patch fixes it too. Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> |
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| boot | ||
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| crypto | ||
| include | ||
| kernel | ||
| kvm | ||
| lib | ||
| math-emu | ||
| mm | ||
| net | ||
| oprofile | ||
| perf | ||
| platforms | ||
| sysdev | ||
| xmon | ||
| Kconfig | ||
| Kconfig.debug | ||
| Makefile | ||
| relocs_check.pl | ||