Blah. The patch [0] I recently sent fixing errors with
in_hugepage_area() and prepare_hugepage_range() for powerpc itself has
an off-by-one bug. Furthermore, the related functions
touches_hugepage_*_range() and within_hugepage_*_range() are also
buggy. Some of the bugs, like those addressed in [0] originated with
commit 7d24f0b8a5 where we tweaked the
semantics of where hugepages are allowed. Other bugs have been there
essentially forever, and are due to the undefined behaviour of '<<'
with shift counts greater than the type width (LOW_ESID_MASK could
return non-zero for high ranges with the right congruences).
The good news is that I now have a testsuite which should pick up
things like this if they creep in again.
[0] "powerpc-fix-for-hugepage-areas-straddling-4gb-boundary"
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Commit 7d24f0b8a5 fixed bugs in the ppc64 SLB
miss handler with respect to hugepage handling, and in the process tweaked
the semantics of the hugepage address masks in mm_context_t.
Unfortunately, it left out a couple of necessary changes to go with that
change. First, the in_hugepage_area() macro was not updated to match,
second prepare_hugepage_range() was not updated to correctly handle
hugepages regions which straddled the 4GB point.
The latter appears only to cause process-hangs when attempting to map such
a region, but the former can cause oopses if a get_user_pages() is
triggered at the wrong point. This patch addresses both bugs.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
With the new powerpc architecture we don't seem to be able to disable huge
pages anymore.
mm/built-in.o(.toc1+0xae0): undefined reference to `HPAGE_SHIFT'
make: *** [.tmp_vmlinux1] Error 1
We seem to need to define HPAGE_SHIFT to something when HUGETLB_PAGE isn't
defined. This patch defines it to PAGE_SHIFT when we have no support.
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Merge asm-ppc/page.h and asm-ppc64/page.h into asm-powerpc/page.h,
asm-powerpc/page_32.h and asm-powerpc/page_64.h
Built for PPC (common_defconfig), with ARCH=powerpc, mostly built with
ARCH=ppc (other things break the build). Built and booted on P5 LPAR
for PPC64 with ARCH=ppc/powerpc (pseries_defconfig). Mostly built for
iSeries powerpc.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
David Gibson
Andy Whitcroft
Michael Ellerman