linux/arch, branch v3.1.9

powerpc: Fix unpaired probe_hcall_entry and probe_hcall_exit

2012-01-12T19:33:14Z

commit e4f387d8db3ba3c2dae4d8bdfe7bb5f4fe1bcb0d upstream. Unpaired calling of probe_hcall_entry and probe_hcall_exit might happen as following, which could cause incorrect preempt count. __trace_hcall_entry => trace_hcall_entry -> probe_hcall_entry => get_cpu_var => preempt_disable __trace_hcall_exit => trace_hcall_exit -> probe_hcall_exit => put_cpu_var => preempt_enable where: A => B and A -> B means A calls B, but => means A will call B through function name, and B will definitely be called. -> means A will call B through function pointer, so B might not be called if the function pointer is not set. So error happens when only one of probe_hcall_entry and probe_hcall_exit get called during a hcall. This patch tries to move the preempt count operations from probe_hcall_entry and probe_hcall_exit to its callers. Reported-by: Paul E. McKenney Signed-off-by: Li Zhong Tested-by: Paul E. McKenney Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Greg Kroah-Hartman

powerpc/time: Handle wrapping of decrementer

2012-01-12T19:33:13Z

commit 37fb9a0231ee43d42d069863bdfd567fca2b61af upstream. When re-enabling interrupts we have code to handle edge sensitive decrementers by resetting the decrementer to 1 whenever it is negative. If interrupts were disabled long enough that the decrementer wrapped to positive we do nothing. This means interrupts can be delayed for a long time until it finally goes negative again. While we hope interrupts are never be disabled long enough for the decrementer to go positive, we have a very good test team that can drive any kernel into the ground. The softlockup data we get back from these fails could be seconds in the future, completely missing the cause of the lockup. We already keep track of the timebase of the next event so use that to work out if we should trigger a decrementer exception. Signed-off-by: Anton Blanchard Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Greg Kroah-Hartman

net: bpf_jit: fix an off-one bug in x86_64 cond jump target

2012-01-06T22:17:26Z

[ Upstream commit a03ffcf873fe0f2565386ca8ef832144c42e67fa ] x86 jump instruction size is 2 or 5 bytes (near/long jump), not 2 or 6 bytes. In case a conditional jump is followed by a long jump, conditional jump target is one byte past the start of target instruction. Signed-off-by: Markus Kötter Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

sparc: Fix handling of orig_i0 wrt. debugging when restarting syscalls.

2012-01-06T22:17:25Z

[ A combination of upstream commits 1d299bc7732c34d85bd43ac1a8745f5a2fed2078 and e88d2468718b0789b4c33da2f7e1cef2a1eee279 ] Although we provide a proper way for a debugger to control whether syscall restart occurs, we run into problems because orig_i0 is not saved and restored properly. Luckily we can solve this problem without having to make debuggers aware of the issue. Across system calls, several registers are considered volatile and can be safely clobbered. Therefore we use the pt_regs save area of one of those registers, %g6, as a place to save and restore orig_i0. Debuggers transparently will do the right thing because they save and restore this register already. Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

sparc64: Fix masking and shifting in VIS fpcmp emulation.

2012-01-06T22:17:25Z

[ Upstream commit 2e8ecdc008a16b9a6c4b9628bb64d0d1c05f9f92 ] Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

sparc32: Correct the return value of memcpy.

2012-01-06T22:17:25Z

[ Upstream commit a52312b88c8103e965979a79a07f6b34af82ca4b ] Properly return the original destination buffer pointer. Signed-off-by: David S. Miller Tested-by: Kjetil Oftedal Signed-off-by: Greg Kroah-Hartman

sparc32: Remove uses of %g7 in memcpy implementation.

2012-01-06T22:17:25Z

[ Upstream commit 21f74d361dfd6a7d0e47574e315f780d8172084a ] This is setting things up so that we can correct the return value, so that it properly returns the original destination buffer pointer. Signed-off-by: David S. Miller Tested-by: Kjetil Oftedal Signed-off-by: Greg Kroah-Hartman

sparc32: Remove non-kernel code from memcpy implementation.

2012-01-06T22:17:24Z

[ Upstream commit 045b7de9ca0cf09f1adc3efa467f668b89238390 ] Signed-off-by: David S. Miller Tested-by: Kjetil Oftedal Signed-off-by: Greg Kroah-Hartman

sparc: Kill custom io_remap_pfn_range().

2012-01-06T22:17:24Z

[ Upstream commit 3e37fd3153ac95088a74f5e7c569f7567e9f993a ] To handle the large physical addresses, just make a simple wrapper around remap_pfn_range() like MIPS does. Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

sparc64: Patch sun4v code sequences properly on module load.

2012-01-06T22:17:24Z

[ Upstream commit 0b64120cceb86e93cb1bda0dc055f13016646907 ] Some of the sun4v code patching occurs in inline functions visible to, and usable by, modules. Therefore we have to patch them up during module load. Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman