kernel/arch/powerpc/include/asm/switch_to.h, branch linux-4.3.y

powerpc: Uncomment and make enable_kernel_vsx() routine available

2015-07-14T06:56:48Z

enable_kernel_vsx() function was commented since anything was using it. However, vmx-crypto driver uses VSX instructions which are only available if VSX is enable. Otherwise it rises an exception oops. This patch uncomment enable_kernel_vsx() routine and makes it available. Signed-off-by: Leonidas S. Barbosa Signed-off-by: Herbert Xu

powerpc/perf: Ensure all EBB register state is cleared on fork()

2014-06-11T07:03:41Z

In commit 330a1eb "Core EBB support for 64-bit book3s" I messed up clear_task_ebb(). It clears some but not all of the task's Event Based Branch (EBB) registers when we duplicate a task struct. That allows a child task to observe the EBBHR & EBBRR of its parent, which it should not be able to do. Fix it by clearing EBBHR & EBBRR. Signed-off-by: Michael Ellerman Cc: stable@vger.kernel.org [v3.11+] Signed-off-by: Benjamin Herrenschmidt

powerpc: Correct DSCR during TM context switch

2014-06-11T07:02:56Z

Correct the DSCR SPR becoming temporarily corrupted if a task is context switched during a transaction. The problem occurs while suspending the task and is caused by saving the DSCR to thread.dscr after it has already been set to the CPU's default value: __switch_to() calls __switch_to_tm() which calls tm_reclaim_task() which calls tm_reclaim_thread() which calls tm_reclaim() where the DSCR is set to the CPU's default __switch_to() calls _switch() where thread.dscr is set to the DSCR When the task is resumed, it's transaction will be doomed (as usual) and the DSCR SPR will be corrupted, although the checkpointed value will be correct. Therefore the DSCR will be immediately corrected by the transaction aborting, unless it has been suspended. In that case the incorrect value can be seen by the task until it resumes the transaction. The fix is to treat the DSCR similarly to the TAR and save it early in __switch_to(). A program exposing the problem is added to the kernel self tests as: tools/testing/selftests/powerpc/tm/tm-resched-dscr. Signed-off-by: Sam Bobroff CC: [v3.10+] Signed-off-by: Benjamin Herrenschmidt

Merge branch 'kvm-ppc-next' of git://github.com/agraf/linux-2.6 into kvm-queue

2014-01-29T17:29:01Z

Conflicts: arch/powerpc/kvm/book3s_hv_rmhandlers.S arch/powerpc/kvm/booke.c

KVM: PPC: Use load_fp/vr_state rather than load_up_fpu/altivec

2014-01-09T09:14:59Z

The load_up_fpu and load_up_altivec functions were never intended to be called from C, and do things like modifying the MSR value in their callers' stack frames, which are assumed to be interrupt frames. In addition, on 32-bit Book S they require the MMU to be off. This makes KVM use the new load_fp_state() and load_vr_state() functions instead of load_up_fpu/altivec. This means we can remove the assembler glue in book3s_rmhandlers.S, and potentially fixes a bug on Book E, where load_up_fpu was called directly from C. Signed-off-by: Paul Mackerras Signed-off-by: Alexander Graf

powerpc/kvm/booke: Fix build break due to stack frame size warning

2013-12-10T23:12:44Z

Commit ce11e48b7fdd256ec68b932a89b397a790566031 ("KVM: PPC: E500: Add userspace debug stub support") added "struct thread_struct" to the stack of kvmppc_vcpu_run(). thread_struct is 1152 bytes on my build, compared to 48 bytes for the recently-introduced "struct debug_reg". Use the latter instead. This fixes the following error: cc1: warnings being treated as errors arch/powerpc/kvm/booke.c: In function 'kvmppc_vcpu_run': arch/powerpc/kvm/booke.c:760:1: error: the frame size of 1424 bytes is larger than 1024 bytes make[2]: *** [arch/powerpc/kvm/booke.o] Error 1 make[1]: *** [arch/powerpc/kvm] Error 2 make[1]: *** Waiting for unfinished jobs.... Signed-off-by: Scott Wood Signed-off-by: Alexander Graf

powerpc: export debug registers save function for KVM

2013-10-18T23:46:18Z

KVM need this function when switching from vcpu to user-space thread. My subsequent patch will use this function. Signed-off-by: Bharat Bhushan Acked-by: Michael Neuling Signed-off-by: Scott Wood

Merge branch 'merge' into next

2013-08-27T05:03:30Z

Merge stuff that already went into Linus via "merge" which are pre-reqs for subsequent patches

powerpc: Remove the empty giveup_fpu() function on 32bit kernel

2013-08-14T04:59:50Z

Instead of implementing an empty giveup_fpu() function for each 32bit processor type, replace them with an unique empty inline function. Signed-off-by: Kevin Hao Signed-off-by: Benjamin Herrenschmidt

powerpc: Make flush_fp_to_thread() nop when CONFIG_PPC_FPU is disabled

2013-08-14T04:59:44Z

In the current kernel, the function flush_fp_to_thread() is not dependent on CONFIG_PPC_FPU. So most invocations of this function is not wrapped by CONFIG_PPC_FPU. Even through we don't really save the FPRs to the thread struct if CONFIG_PPC_FPU is not enabled, but there does have some runtime overhead such as the check for tsk->thread.regs and preempt disable and enable. It really make no sense to do that. So make it a nop when CONFIG_PPC_FPU is disabled. Also remove the wrapped #ifdef CONFIG_PPC_FPU when invoking this function. Signed-off-by: Kevin Hao Signed-off-by: Benjamin Herrenschmidt