BMC/Intel-BMC/linux.git/arch/s390/kernel/traps.c, branch dev

s390: adapt entry.S to the move of thread_struct

2015-07-20T11:22:18+00:00

git commit 0c8c0f03e3a292e031596484275c14cf39c0ab7a "x86/fpu, sched: Dynamically allocate 'struct fpu'" moved the thread_struct to the end of the task_struct. This causes some of the offsets used in entry.S to overflow their instruction operand field. To fix this use aghi to create a dedicated pointer for the thread_struct. Signed-off-by: Martin Schwidefsky

s390/traps: panic() instead of die() on translation exception

2015-03-25T10:49:38+00:00

In case of a translation exception the page tables are corrupted. If the exception handler then calls die() which again calls show_regs() -> show_code() -> copy_from_user(), the kernel may access the same memory location again and generates yet another translation exception. Which in turn will lead to a deadlock on the die_lock spinlock, which the kernel tries to grab recursively. Given that the page tables are corrupted anyway, if we see such an exception, let's simply panic. Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky

s390: remove 31 bit support

2015-03-25T10:49:33+00:00

Remove the 31 bit support in order to reduce maintenance cost and effectively remove dead code. Since a couple of years there is no distribution left that comes with a 31 bit kernel. The 31 bit kernel also has been broken since more than a year before anybody noticed. In addition I added a removal warning to the kernel shown at ipl for 5 minutes: a960062e5826 ("s390: add 31 bit warning message") which let everybody know about the plan to remove 31 bit code. We didn't get any response. Given that the last 31 bit only machine was introduced in 1999 let's remove the code. Anybody with 31 bit user space code can still use the compat mode. Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky

s390/traps: die on translation exceptions

2014-11-21T07:49:33+00:00

Translation exceptions should never happen, since that implies that either we screwed up the page tables or missed to properly flush the TLB. In both cases we should not just simply kill user space or walk the kernel exception tables. Instead an oops or a panic (panic_on_oops) is the better answer. Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky

s390/traps: print interrupt code and instruction length code

2014-11-21T07:49:30+00:00

It always confuses me to see the mixed instruction length code and interruption code on user space faults, while the message clearly says it is the interruption code. So split the value and print both values separately. Also add the ILC output to the die() message, so thar user and kernel space faults contain the same information. Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky

s390/kprobes: make use of NOKPROBE_SYMBOL()

2014-10-27T12:27:28+00:00

Use NOKPROBE_SYMBOL() instead of __kprobes annotation. Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky

s390: add support for vector extension

2014-10-09T07:14:13+00:00

The vector extension introduces 32 128-bit vector registers and a set of instruction to operate on the vector registers. The kernel can control the use of vector registers for the problem state program with a bit in control register 0. Once enabled for a process the kernel needs to retain the content of the vector registers on context switch. The signal frame is extended to include the vector registers. Two new register sets NT_S390_VXRS_LOW and NT_S390_VXRS_HIGH are added to the regset interface for the debugger and core dumps. Signed-off-by: Martin Schwidefsky

s390/uprobes: architecture backend for uprobes

2014-09-25T08:52:17+00:00

Signed-off-by: Jan Willeke Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky

s390/dumpstack: fix call chain walking

2013-04-17T12:07:28+00:00

dumpstack() did not always print a sane callchain when being called. The reason is that show_trace() accessed register 15 directly to get the current stack pointer and passed that pointer to __show_trace() which expects a valid stack frame pointer as argument. However due to tail call optimization the stack frame may not exist anymore when __show_trace() gets called and therefore an invalid stack frame pointer gets passed. To prevent that disable tail call optimization for call chain walking functions. So move all the show_* functions to a dumpstack.c file like other architectures have it already and add a -fno-optimize-sibling-calls compile flag to both dumpstack.c and stacktrace.c to prevent tail call optimization. Fixes callchains that looked e.g. like this: [ 12.868258] Call Trace: [ 12.868262] ([<0000000000008000>] 0x8000) Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky

taint: add explicit flag to show whether lock dep is still OK.

2013-01-21T06:47:57+00:00

Fix up all callers as they were before, with make one change: an unsigned module taints the kernel, but doesn't turn off lockdep. Signed-off-by: Rusty Russell