On 08/06/2015 03:02 PM, Juergen Gross wrote:

On 08/06/2015 02:46 PM, Vlastimil Babka wrote:

quoted

On 07/17/2015 06:51 AM, Juergen Gross wrote:

... and here for !CONFIG_MMU.

So, what about CONFIG_MMU && !FIXMAP_PAGE_RO combinations? Which
translates to CONFIG_MMU && !PAGE_KERNEL_RO. Maybe they don't exist, but
then it's still awkward to see the combination in the code left
unimplemented.

At least there are some architectures without #define PAGE_KERNEL_RO but
testing CONFIG_MMU (arm, m68k, xtensa).

quoted

Would it be perhaps simpler to assume the same thing as in
drivers/base/firmware_class.c ?

/* Some architectures don't have PAGE_KERNEL_RO */
#ifndef PAGE_KERNEL_RO
#define PAGE_KERNEL_RO PAGE_KERNEL
#endif

Or would it be dangerous here to silently lose the read-only protection?

The only reason to use this function instead of early_memremap() is the
mandatory read-only mapping. My intention was to let the build fail in
case it is being used but not implemented. An architecture requiring the
function but having no PAGE_KERNEL_RO still can define FIXMAP_PAGE_RO.

OK, in that case

Acked-by: Vlastimil Babka <redacted>

Juergen

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>