kernel.git/arch/s390/kernel/setup.c, branch linux-3.19.y

s390/ftrace,kprobes: allow to patch first instruction

2014-10-27T12:27:27Z

If the function tracer is enabled, allow to set kprobes on the first instruction of a function (which is the function trace caller): If no kprobe is set handling of enabling and disabling function tracing of a function simply patches the first instruction. Either it is a nop (right now it's an unconditional branch, which skips the mcount block), or it's a branch to the ftrace_caller() function. If a kprobe is being placed on a function tracer calling instruction we encode if we actually have a nop or branch in the remaining bytes after the breakpoint instruction (illegal opcode). This is possible, since the size of the instruction used for the nop and branch is six bytes, while the size of the breakpoint is only two bytes. Therefore the first two bytes contain the illegal opcode and the last four bytes contain either "0" for nop or "1" for branch. The kprobes code will then execute/simulate the correct instruction. Instruction patching for kprobes and function tracer is always done with stop_machine(). Therefore we don't have any races where an instruction is patched concurrently on a different cpu. Besides that also the program check handler which executes the function trace caller instruction won't be executed concurrently to any stop_machine() execution. This allows to keep full fault based kprobes handling which generates correct pt_regs contents automatically. Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky

s390: add support for vector extension

2014-10-09T07:14:13Z

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/setup: correct 4-level kernel page table detection

2014-09-26T10:22:42Z

Fix calculation to decide if a 4-level kernel page table is required. Git commit c972cc60c23f5a63 "s390/vmalloc: have separate modules area" added the separate module area which reduces the size of the vmalloc area but fails to take it into account for the 3 vs 4 level page table decision. Signed-off-by: Martin Schwidefsky

s390: add system information as device randomness

2014-08-12T11:00:07Z

The virtual-machine cpu information data block and the cpu-id of the boot cpu can be used as source of device randomness. Signed-off-by: Martin Schwidefsky

s390/kdump: Return NOTIFY_OK for all actions other than MEM_GOING_OFFLINE

2014-07-22T07:26:20Z

We only have to check kdump memory for the MEM_GOING_OFFLINE action. Therefore skip the test and return NOTIFY_OK for all other memory hotplug actions. Signed-off-by: Michael Holzheu Signed-off-by: Martin Schwidefsky

s390/dump: Remove CONFIG_ZFCPDUMP

2014-05-20T06:58:43Z

Currently there are two s390 kernel dump config options "CONFIG_ZFCPDUMP" and "CONFIG_CRASH_DUMP". In order to keep things simple and because the "CONFIG_ZFCPDUMP" option already has a dependency to "CONFIG_CRASH_DUMP" remove the CONFIG_ZFCPDUMP option. Signed-off-by: Michael Holzheu Reviewed-by: Eric Farman Signed-off-by: Martin Schwidefsky

s390/spinlock: optimize spinlock code sequence

2014-05-20T06:58:42Z

Use lowcore constant to improve the code generated for spinlocks. [ Martin Schwidefsky: patch breakdown and code beautification ] Signed-off-by: Philipp Hachtmann Signed-off-by: Martin Schwidefsky

s390/mm: Convert bootmem to memblock

2014-05-20T06:58:40Z

The original bootmem allocator is getting replaced by memblock. To cover the needs of the s390 kdump implementation the physical memory list is used. With this patch the bootmem allocator and its bitmaps are completely removed from s390. Signed-off-by: Philipp Hachtmann Signed-off-by: Martin Schwidefsky

s390: add 31 bit warning message

2014-04-11T11:53:31Z

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

s390/uaccess: remove dead kernel parameter 'user_mode='

2014-02-21T07:50:16Z

Remove another leftover from the time when we supported running user space in either home or primary address space. Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky