mirror of https://gitee.com/openkylin/linux.git
1427130425
PAGE_KERNEL_RO is not available on all architectures, so its use in the new AR code broke compilation on sparc64. Because the read-only mapping was just a debugging aid, just use PAGE_KERNEL instead. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> James Bottomley wrote: > On Thu, 2011-01-13 at 08:27 +0100, Clemens Ladisch wrote: >> firewire: ohci: fix compilation on arches without PAGE_KERNEL_RO, e.g. sparc >> >> PAGE_KERNEL_RO is not available on all architectures, so its use in the >> new AR code broke compilation on sparc64. >> >> Because the R/O mapping is only used to catch drivers that try to write >> to the reception buffer and not actually required for correct operation, >> we can just use a normal PAGE_KERNEL mapping where _RO is not available. [...] >> +/* >> + * For archs where PAGE_KERNEL_RO is not supported; >> + * mapping the AR buffers readonly for the CPU is just a debugging aid. >> + */ >> +#ifndef PAGE_KERNEL_RO >> +#define PAGE_KERNEL_RO PAGE_KERNEL >> +#endif > > This might cause interesting issues on sparc64 if it ever acquired a > PAGE_KERNEL_RO. Sparc64 has extern pgprot_t for it's PAGE_KERNEL types > rather than #defines, so the #ifdef check wouldn't see this. > > I think either PAGE_PROT_RO becomes part of our arch API (so all > architectures are forced to add it), or, if it's not part of the API, > ohci isn't entitled to use it. The latter seems simplest since you have > no real use for write protection anyway. Reported-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> |
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| .. | ||
| Kconfig | ||
| Makefile | ||
| core-card.c | ||
| core-cdev.c | ||
| core-device.c | ||
| core-iso.c | ||
| core-topology.c | ||
| core-transaction.c | ||
| core.h | ||
| init_ohci1394_dma.c | ||
| net.c | ||
| nosy-user.h | ||
| nosy.c | ||
| nosy.h | ||
| ohci.c | ||
| ohci.h | ||
| sbp2.c | ||