linux/arch, branch v3.4.66

tile: use a more conservative __my_cpu_offset in CONFIG_PREEMPT

2013-10-13T22:42:50Z

commit f862eefec0b68e099a9fa58d3761ffb10bad97e1 upstream. It turns out the kernel relies on barrier() to force a reload of the percpu offset value. Since we can't easily modify the definition of barrier() to include "tp" as an output register, we instead provide a definition of __my_cpu_offset as extended assembly that includes a fake stack read to hazard against barrier(), forcing gcc to know that it must reread "tp" and recompute anything based on "tp" after a barrier. This fixes observed hangs in the slub allocator when we are looping on a percpu cmpxchg_double. A similar fix for ARMv7 was made in June in change 509eb76ebf97. Signed-off-by: Chris Metcalf Signed-off-by: Greg Kroah-Hartman

mm, show_mem: suppress page counts in non-blockable contexts

2013-10-13T22:42:49Z

commit 4b59e6c4730978679b414a8da61514a2518da512 upstream. On large systems with a lot of memory, walking all RAM to determine page types may take a half second or even more. In non-blockable contexts, the page allocator will emit a page allocation failure warning unless __GFP_NOWARN is specified. In such contexts, irqs are typically disabled and such a lengthy delay may even result in NMI watchdog timeouts. To fix this, suppress the page walk in such contexts when printing the page allocation failure warning. Signed-off-by: David Rientjes Cc: Mel Gorman Acked-by: Michal Hocko Cc: Dave Hansen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Cc: Xishi Qiu Signed-off-by: Greg Kroah-Hartman

sparc32: Fix exit flag passed from traced sys_sigreturn

2013-10-13T22:42:49Z

[ Upstream commit 7a3b0f89e3fea680f93932691ca41a68eee7ab5e ] Pass 1 in %o1 to indicate that syscall_trace accounts exit. Signed-off-by: Kirill Tkhai CC: David Miller Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

sparc64: Fix not SRA'ed %o5 in 32-bit traced syscall

2013-10-13T22:42:49Z

[ Upstream commit ab2abda6377723e0d5fbbfe5f5aa16a5523344d1 ] (From v1 to v2: changed comment) On the way linux_sparc_syscall32->linux_syscall_trace32->goto 2f, register %o5 doesn't clear its second 32-bit. Fix that. Signed-off-by: Kirill Tkhai CC: David Miller Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

sparc64: Fix off by one in trampoline TLB mapping installation loop.

2013-10-13T22:42:49Z

[ Upstream commit 63d499662aeec1864ec36d042aca8184ea6a938e ] Reported-by: Kirill Tkhai Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

sparc64: Remove RWSEM export leftovers

2013-10-13T22:42:49Z

[ Upstream commit 61d9b9355b0d427bd1e732bd54628ff9103e496f ] The functions __down_read __down_read_trylock __down_write __down_write_trylock __up_read __up_write __downgrade_write are implemented inline, so remove corresponding EXPORT_SYMBOLs (They lead to compile errors on RT kernel). Signed-off-by: Kirill Tkhai CC: David Miller Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

sparc64: Fix ITLB handler of null page

2013-10-13T22:42:49Z

[ Upstream commit 1c2696cdaad84580545a2e9c0879ff597880b1a9 ] 1)Use kvmap_itlb_longpath instead of kvmap_dtlb_longpath. 2)Handle page #0 only, don't handle page #1: bleu -> blu (KERNBASE is 0x400000, so #1 does not exist too. But everything is possible in the future. Fix to not to have problems later.) 3)Remove unused kvmap_itlb_nonlinear. Signed-off-by: Kirill Tkhai CC: David Miller Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

powerpc: Fix parameter clobber in csum_partial_copy_generic()

2013-10-13T22:42:48Z

commit d9813c3681a36774b254c0cdc9cce53c9e22c756 upstream. The csum_partial_copy_generic() uses register r7 to adjust the remaining bytes to process. Unfortunately, r7 also holds a parameter, namely the address of the flag to set in case of access exceptions while reading the source buffer. Lacking a quantum implementation of PowerPC, this commit instead uses register r9 to do the adjusting, leaving r7's pointer uncorrupted. Signed-off-by: Paul E. McKenney Signed-off-by: Anton Blanchard Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Greg Kroah-Hartman

powerpc/vio: Fix modalias_show return values

2013-10-13T22:42:48Z

commit e82b89a6f19bae73fb064d1b3dd91fcefbb478f4 upstream. modalias_show() should return an empty string on error, not -ENODEV. This causes the following false and annoying error: > find /sys/devices -name modalias -print0 | xargs -0 cat >/dev/null cat: /sys/devices/vio/4000/modalias: No such device cat: /sys/devices/vio/4001/modalias: No such device cat: /sys/devices/vio/4002/modalias: No such device cat: /sys/devices/vio/4004/modalias: No such device cat: /sys/devices/vio/modalias: No such device Signed-off-by: Prarit Bhargava Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Greg Kroah-Hartman

powerpc/iommu: Use GFP_KERNEL instead of GFP_ATOMIC in iommu_init_table()

2013-10-13T22:42:48Z

commit 1cf389df090194a0976dc867b7fffe99d9d490cb upstream. Under heavy (DLPAR?) stress, we tripped this panic() in arch/powerpc/kernel/iommu.c::iommu_init_table(): page = alloc_pages_node(nid, GFP_ATOMIC, get_order(sz)); if (!page) panic("iommu_init_table: Can't allocate %ld bytes\n", sz); Before the panic() we got a page allocation failure for an order-2 allocation. There appears to be memory free, but perhaps not in the ATOMIC context. I looked through all the call-sites of iommu_init_table() and didn't see any obvious reason to need an ATOMIC allocation. Most call-sites in fact have an explicit GFP_KERNEL allocation shortly before the call to iommu_init_table(), indicating we are not in an atomic context. There is some indirection for some paths, but I didn't see any locks indicating that GFP_KERNEL is inappropriate. With this change under the same conditions, we have not been able to reproduce the panic. Signed-off-by: Nishanth Aravamudan Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Greg Kroah-Hartman