kernel.git/arch/powerpc/kernel/traps.c, branch linux-3.8.y

powerpc: Emulate non privileged DSCR read and write

2013-05-11T20:53:50Z

commit 73d2fb758e678c93bc76d40876c2359f0729b0ef upstream. POWER8 allows read and write of the DSCR in userspace. We added kernel emulation so applications could always use the instructions regardless of the CPU type. Unfortunately there are two SPRs for the DSCR and we only added emulation for the privileged one. Add code to match the non privileged one. A simple test was created to verify the fix: http://ozlabs.org/~anton/junkcode/user_dscr_test.c Without the patch we get a SIGILL and it passes with the patch. Signed-off-by: Anton Blanchard Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Greg Kroah-Hartman

Merge branch 'merge' into next

2012-09-06T23:48:59Z

Brings in various bug fixes from 3.6-rcX

powerpc: Keep thread.dscr and thread.dscr_inherit in sync

2012-09-05T06:05:21Z

When we update the DSCR either via emulation of mtspr(DSCR) or via a change to dscr_default in sysfs we don't update thread.dscr. We will eventually update it at context switch time but there is a period where thread.dscr is incorrect. If we fork at this point we will copy the old value of thread.dscr into the child. To avoid this, always keep thread.dscr in sync with reality. This issue was found with the following testcase: http://ozlabs.org/~anton/junkcode/dscr_inherit_test.c Signed-off-by: Anton Blanchard Cc: # 3.0+ Signed-off-by: Benjamin Herrenschmidt

powerpc: Add trap_nr to thread_struct

2012-09-05T05:19:36Z

Add thread_struct.trap_nr and use it to store the last exception the thread experienced. In this patch, we populate the field at various places where we force_sig_info() to the process. This is also used in uprobes to determine if the probed instruction caused an exception. Signed-off-by: Ananth N Mavinakayanahalli Signed-off-by: Benjamin Herrenschmidt

powerpc/irq: Make alignment & program interrupt behave the same

2012-05-08T23:42:33Z

Alignment was the last user of the ENABLE_INTS macro, which we can now remove. All non-syscall exceptions now disable interrupts on entry, they get re-enabled conditionally from C code. Don't unconditionally re-enable in program check either, check the original context. Signed-off-by: Benjamin Herrenschmidt

Disintegrate asm/system.h for PowerPC

2012-03-28T17:30:02Z

Disintegrate asm/system.h for PowerPC. Signed-off-by: David Howells Acked-by: Benjamin Herrenschmidt cc: linuxppc-dev@lists.ozlabs.org

powerpc: Disable interrupts in 64-bit kernel FP and vector faults

2012-03-08T23:55:10Z

If we get a floating point, altivec or vsx unavaible interrupt in kernel, we trigger a kernel error. There is no point preserving the interrupt state, in fact, that can even make debugging harder as the processor state might change (we may even preempt) between taking the exception and landing in a debugger. So just make those 3 disable interrupts unconditionally. Signed-off-by: Benjamin Herrenschmidt --- v2: On BookE only disable when hitting the kernel unavailable path, otherwise it will fail to restore softe as fast_exception_return doesn't do it.

fadump: Convert firmware-assisted cpu state dump data into elf notes.

2012-02-22T23:50:01Z

When registered for firmware assisted dump on powerpc, firmware preserves the registers for the active CPUs during a system crash. This patch reads the cpu register data stored in Firmware-assisted dump format (except for crashing cpu) and converts it into elf notes and updates the PT_NOTE program header accordingly. The exact register state for crashing cpu is saved to fadump crash info structure in scratch area during crash_fadump() and read during second kernel boot. Signed-off-by: Mahesh Salgaonkar Signed-off-by: Benjamin Herrenschmidt

powerpc: Rework die()

2011-12-08T03:02:23Z

Our die() code was based off a very old x86 version. Update it to mirror the current x86 code. Signed-off-by: Anton Blanchard Signed-off-by: Benjamin Herrenschmidt

powerpc: Remove broken and complicated kdump system reset code

2011-12-08T03:02:22Z

We have a lot of complicated logic that handles possible recursion between kdump and a system reset exception. We can solve this in a much simpler way using the same setjmp/longjmp tricks xmon does. As a first step, this patch removes the old system reset code. Signed-off-by: Anton Blanchard Signed-off-by: Benjamin Herrenschmidt