Paul Mackerras bdbc29c19b powerpc: Work around gcc miscompilation of __pa() on 64-bit ... On 64-bit, __pa(&static_var) gets miscompiled by recent versions of gcc as something like: addis 3,2,.LANCHOR1+4611686018427387904@toc@ha addi 3,3,.LANCHOR1+4611686018427387904@toc@l This ends up effectively ignoring the offset, since its bottom 32 bits are zero, and means that the result of __pa() still has 0xC in the top nibble. This happens with gcc 4.8.1, at least. To work around this, for 64-bit we make __pa() use an AND operator, and for symmetry, we make __va() use an OR operator. Using an AND operator rather than a subtraction ends up with slightly shorter code since it can be done with a single clrldi instruction, whereas it takes three instructions to form the constant (-PAGE_OFFSET) and add it on. (Note that MEMORY_START is always 0 on 64-bit.) CC: <stable@vger.kernel.org> Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>		2013-08-27 16:59:30 +10:00
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asm	powerpc: Work around gcc miscompilation of __pa() on 64-bit	2013-08-27 16:59:30 +10:00
uapi/asm	powerpc/perf: Export PERF_EVENT_CONFIG_EBB_SHIFT to userspace	2013-08-01 13:11:46 +10:00