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

s390/kdump: fix nosmt kernel parameter

2015-06-25T07:39:26+00:00

It turned out that SIGP set-multi-threading can only be done once. Therefore switching to a different MT level after switching to sclp.mtid_prev in the dump case fails. As a symptom specifying the "nosmt" parameter currently fails for the kdump kernel and the kernel starts with multi-threading enabled. So fix this and issue diag 308 subcode 1 call after collecting the CPU states for the dump. Also enhance the diag308_reset() function to be usable also with enabled lowcore protection and prefix register != 0. After the reset it is possible to switch the MT level again. We have to do the reset very early in order not to kill the already initialized console. Therefore instead of kmalloc() the corresponding memblock functions have to be used. To avoid copying the sclp cpu code into sclp_early, we now use the simple sigp loop method for CPU detection. Signed-off-by: Michael Holzheu Signed-off-by: Martin Schwidefsky

s390/kdump: fix REGSET_VX_LOW vector register ELF notes

2015-06-25T07:39:18+00:00

The REGSET_VX_LOW ELF notes should contain the lower 64 bit halfes of the first sixteen 128 bit vector registers. Unfortunately currently we copy the upper halfes. Fix this and correctly copy the lower halfes. Fixes: a62bc0739253 ("s390/kdump: add support for vector extension") Cc: stable@vger.kernel.org # 3.18+ Signed-off-by: Michael Holzheu Signed-off-by: Martin Schwidefsky

mm/memblock: add extra "flags" to memblock to allow selection of memory based on attribute

2015-06-25T00:49:44+00:00

Some high end Intel Xeon systems report uncorrectable memory errors as a recoverable machine check. Linux has included code for some time to process these and just signal the affected processes (or even recover completely if the error was in a read only page that can be replaced by reading from disk). But we have no recovery path for errors encountered during kernel code execution. Except for some very specific cases were are unlikely to ever be able to recover. Enter memory mirroring. Actually 3rd generation of memory mirroing. Gen1: All memory is mirrored Pro: No s/w enabling - h/w just gets good data from other side of the mirror Con: Halves effective memory capacity available to OS/applications Gen2: Partial memory mirror - just mirror memory begind some memory controllers Pro: Keep more of the capacity Con: Nightmare to enable. Have to choose between allocating from mirrored memory for safety vs. NUMA local memory for performance Gen3: Address range partial memory mirror - some mirror on each memory controller Pro: Can tune the amount of mirror and keep NUMA performance Con: I have to write memory management code to implement The current plan is just to use mirrored memory for kernel allocations. This has been broken into two phases: 1) This patch series - find the mirrored memory, use it for boot time allocations 2) Wade into mm/page_alloc.c and define a ZONE_MIRROR to pick up the unused mirrored memory from mm/memblock.c and only give it out to select kernel allocations (this is still being scoped because page_alloc.c is scary). This patch (of 3): Add extra "flags" to memblock to allow selection of memory based on attribute. No functional changes Signed-off-by: Tony Luck Cc: Xishi Qiu Cc: Hanjun Guo Cc: Xiexiuqi Cc: Ingo Molnar Cc: Thomas Gleixner Cc: "H. Peter Anvin" Cc: Yinghai Lu Cc: Naoya Horiguchi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

s390/sclp: unify basic sclp access by exposing "struct sclp"

2015-05-13T07:58:17+00:00

Let's unify basic access to sclp fields by storing the data in an external struct in asm/sclp.h. The values can now directly be accessed by other components, so there is no need for most accessor functions and external variables anymore. The mtid, mtid_max and facility part will be cleaned up separately. Acked-by: Martin Schwidefsky Signed-off-by: David Hildenbrand Signed-off-by: Martin Schwidefsky

s390/kdump: add support for vector extension

2014-10-09T07:14:16+00:00

With this patch for kdump the s390 vector registers are stored into the prepared save areas in the old kernel and into the REGSET_VX_LOW and REGSET_VX_HIGH ELF notes for /proc/vmcore in the new kernel. The NT_S390_VXRS_LOW note contains the lower halves of the first 16 vector registers 0-15. The higher halves are stored in the floating point register ELF note. The NT_S390_VXRS_HIGH contains the full vector registers 16-31. The kernel provides a save area for storing vector register in case of machine checks. A pointer to this save are is stored in the CPU lowcore at offset 0x11b0. This save area is also used to save the registers for kdump. In case of a dumped crashed kdump those areas are used to extract the registers of the production system. The vector registers for remote CPUs are stored using the "store additional status at address" SIGP. For the dump CPU the vector registers are stored with the VSTM instruction. With this patch also zfcpdump stores the vector registers. Reviewed-by: Heiko Carstens Signed-off-by: Michael Holzheu Signed-off-by: Martin Schwidefsky

s390/mm: Convert bootmem to memblock

2014-05-20T06:58:40+00:00

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/sclp: Determine HSA size dynamically for zfcpdump

2013-11-15T13:08:40+00:00

Currently we have hardcoded the HSA size to 32 MiB. With this patch the HSA size is determined dynamically via SCLP in early.c. Reviewed-by: Heiko Carstens Signed-off-by: Michael Holzheu Signed-off-by: Martin Schwidefsky

s390: Remove zfcpdump NR_CPUS dependency

2013-10-24T15:17:04+00:00

Currently zfpcdump can only collect registers for up to CONFIG_NR_CPUS CPUss. This dependency is not necessary. So remove it by dynamically allocating the save area array. Signed-off-by: Michael Holzheu Reviewed-by: Heiko Carstens Signed-off-by: Martin Schwidefsky

s390/crashdump: remove unused variable

2013-10-24T15:17:02+00:00

Get rid of this compile warning: arch/s390/kernel/crash_dump.c: In function 'copy_from_realmem': arch/s390/kernel/crash_dump.c:48:6: warning: unused variable 'rc' [-Wunused-variable] int rc; ^ Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky

s390: Allow vmalloc target buffers for copy_from_oldmem()

2013-09-30T11:04:40+00:00

Currently copy_from_oldmem() is not able to copy to virtual memory. When using kexec pre-allocated ELF header, copy_from_oldmem() is used to copy the ELF notes information to vmalloc buffers. So fix this and use the new function copy_from_realmem() that allows copying also to vmalloc memory. Signed-off-by: Michael Holzheu Signed-off-by: Martin Schwidefsky