powerpc/eeh: Handle hugepages in ioremap space
In commit 4a7b06c157a2 ("powerpc/eeh: Handle hugepages in ioremap space") support for using hugepages in the vmalloc and ioremap areas was enabled for radix. Unfortunately this broke EEH MMIO error checking. Detection works by inserting a hook which checks the results of the ioreadXX() set of functions. When a read returns a 0xFFs response we need to check for an error which we do by mapping the (virtual) MMIO address back to a physical address, then mapping physical address to a PCI device via an interval tree. When translating virt -> phys we currently assume the ioremap space is only populated by PAGE_SIZE mappings. If a hugepage mapping is found we emit a WARN_ON(), but otherwise handles the check as though a normal page was found. In pathalogical cases such as copying a buffer containing a lot of 0xFFs from BAR memory this can result in the system not booting because it's too busy printing WARN_ON()s. There's no real reason to assume huge pages can't be present and we're prefectly capable of handling them, so do that. Fixes: 4a7b06c157a2 ("powerpc/eeh: Handle hugepages in ioremap space") Reported-by: Sachin Sant <sachinp@linux.vnet.ibm.com> Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Tested-by: Sachin Sant <sachinp@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190710150517.27114-1-oohall@gmail.com
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