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* s390: simplify disabled_waitMartin Schwidefsky2019-05-021-2/+2
| | | | | | | | | | | | | | | | | | | The disabled_wait() function uses its argument as the PSW address when it stops the CPU with a wait PSW that is disabled for interrupts. The different callers sometimes use a specific number like 0xdeadbeef to indicate a specific failure, the early boot code uses 0 and some other calls sites use __builtin_return_address(0). At the time a dump is created the current PSW and the registers of a CPU are written to lowcore to make them avaiable to the dump analysis tool. For a CPU stopped with disabled_wait the PSW and the registers do not really make sense together, the PSW address does not point to the function the registers belong to. Simplify disabled_wait() by using _THIS_IP_ for the PSW address and drop the argument to the function. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/unwind: introduce stack unwind APIMartin Schwidefsky2019-05-021-0/+1
| | | | | | | | | | | | | | | | | | Rework the dump_trace() stack unwinder interface to support different unwinding algorithms. The new interface looks like this: struct unwind_state state; unwind_for_each_frame(&state, task, regs, start_stack) do_something(state.sp, state.ip, state.reliable); The unwind_bc.c file contains the implementation for the classic back-chain unwinder. One positive side effect of the new code is it now handles ftraced functions gracefully. It prints the real name of the return function instead of 'return_to_handler'. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/kernel: add support for kernel address space layout randomization (KASLR)Gerald Schaefer2019-04-291-0/+1
| | | | | | | | | | | | This patch adds support for relocating the kernel to a random address. The random kernel offset is obtained from cpacf, using either TRNG, PRNO, or KMC_PRNG, depending on supported MSA level. KERNELOFFSET is added to vmcoreinfo, for crash --kaslr support. Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Reviewed-by: Philipp Rudo <prudo@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/kernel: introduce .dma sectionsGerald Schaefer2019-04-291-0/+2
| | | | | | | | | | | | | | | | | | | | | | | With a relocatable kernel that could reside at any place in memory, code and data that has to stay below 2 GB needs special handling. This patch introduces .dma sections for such text, data and ex_table. The sections will be part of the decompressor kernel, so they will not be relocated and stay below 2 GB. Their location is passed over to the decompressed / relocated kernel via the .boot.preserved.data section. The duald and aste for control register setup also need to stay below 2 GB, so move the setup code from arch/s390/kernel/head64.S to arch/s390/boot/head.S. The duct and linkage_stack could reside above 2 GB, but their content has to be preserved for the decompresed kernel, so they are also moved into the .dma section. The start and end address of the .dma sections is added to vmcoreinfo, for crash support, to help debugging in case the kernel crashed there. Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Reviewed-by: Philipp Rudo <prudo@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390: add support for virtually mapped kernel stacksMartin Schwidefsky2018-10-091-4/+13
| | | | | | | | | | | | | | | | | | | | | With virtually mapped kernel stacks the kernel stack overflow detection is now fault based, every stack has a guard page in the vmalloc space. The panic_stack is renamed to nodat_stack and is used for all function that need to run without DAT, e.g. memcpy_real or do_start_kdump. The main effect is a reduction in the kernel image size as with vmap stacks the old style overflow checking that adds two instructions per function is not needed anymore. Result from bloat-o-meter: add/remove: 20/1 grow/shrink: 13/26854 up/down: 2198/-216240 (-214042) In regard to performance the micro-benchmark for fork has a hit of a few microseconds, allocating 4 pages in vmalloc space is more expensive compare to an order-2 page allocation. But with real workload I could not find a noticeable difference. Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/ipl: correct kdump reipl block checksum calculationVasily Gorbik2018-04-101-0/+1
| | | | | | | | | | | | | | | | | | | | | | s390 kdump reipl implementation relies on os_info kernel structure residing in old memory being dumped. os_info contains reipl block, which is used (if valid) by the kdump kernel for reipl parameters. The problem is that the reipl block and its checksum inside os_info is updated only when /sys/firmware/reipl/reipl_type is written. This sets an offset of a reipl block for "reipl_type" and re-calculates reipl block checksum. Any further alteration of values under /sys/firmware/reipl/{reipl_type}/ without subsequent write to /sys/firmware/reipl/reipl_type lead to incorrect os_info reipl block checksum. In such a case kdump kernel ignores it and reboots using default logic. To fix this, os_info reipl block update is moved right before kdump execution. Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390: assume diag308 set always worksVasily Gorbik2018-04-101-1/+0
| | | | | | | | | | | | | | diag308 set has been available for many machine generations, and alternative reipl code paths has not been exercised and seems to be broken without noticing for a while now. So, cleaning up all obsolete reipl methods except currently used ones, assuming that diag308 set always works. Also removing not longer needed reset callbacks. Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* Merge branch 'for-linus' of ↵Linus Torvalds2017-11-131-12/+10
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 updates from Heiko Carstens: "Since Martin is on vacation you get the s390 pull request for the v4.15 merge window this time from me. Besides a lot of cleanups and bug fixes these are the most important changes: - a new regset for runtime instrumentation registers - hardware accelerated AES-GCM support for the aes_s390 module - support for the new CEX6S crypto cards - support for FORTIFY_SOURCE - addition of missing z13 and new z14 instructions to the in-kernel disassembler - generate opcode tables for the in-kernel disassembler out of a simple text file instead of having to manually maintain those tables - fast memset16, memset32 and memset64 implementations - removal of named saved segment support - hardware counter support for z14 - queued spinlocks and queued rwlocks implementations for s390 - use the stack_depth tracking feature for s390 BPF JIT - a new s390_sthyi system call which emulates the sthyi (store hypervisor information) instruction - removal of the old KVM virtio transport - an s390 specific CPU alternatives implementation which is used in the new spinlock code" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (88 commits) MAINTAINERS: add virtio-ccw.h to virtio/s390 section s390/noexec: execute kexec datamover without DAT s390: fix transactional execution control register handling s390/bpf: take advantage of stack_depth tracking s390: simplify transactional execution elf hwcap handling s390/zcrypt: Rework struct ap_qact_ap_info. s390/virtio: remove unused header file kvm_virtio.h s390: avoid undefined behaviour s390/disassembler: generate opcode tables from text file s390/disassembler: remove insn_to_mnemonic() s390/dasd: avoid calling do_gettimeofday() s390: vfio-ccw: Do not attempt to free no-op, test and tic cda. s390: remove named saved segment support s390/archrandom: Reconsider s390 arch random implementation s390/pci: do not require AIS facility s390/qdio: sanitize put_indicator s390/qdio: use atomic_cmpxchg s390/nmi: avoid using long-displacement facility s390: pass endianness info to sparse s390/decompressor: remove informational messages ...
| * s390/noexec: execute kexec datamover without DATHeiko Carstens2017-11-101-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Rebooting into a new kernel with kexec fails (system dies) if tried on a machine that has no-execute support. Reason for this is that the so called datamover code gets executed with DAT on (MMU is active) and the page that contains the datamover is marked as non-executable. Therefore when branching into the datamover an unexpected program check happens and afterwards the machine is dead. This can be simply avoided by disabling DAT, which also disables any no-execute checks, just before the datamover gets executed. In fact the first thing done by the datamover is to disable DAT. The code in the datamover that disables DAT can be removed as well. Thanks to Michael Holzheu and Gerald Schaefer for tracking this down. Reviewed-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Reviewed-by: Philipp Rudo <prudo@linux.vnet.ibm.com> Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Fixes: 57d7f939e7bd ("s390: add no-execute support") Cc: <stable@vger.kernel.org> # v4.11+ Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
| * s390: remove named saved segment supportHeiko Carstens2017-11-081-4/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Remove the support to create a z/VM named saved segment (NSS). This feature is not supported since quite a while in favour of jump labels, function tracing and (now) CPU alternatives. All of these features require to write to the kernel text section which is not possible if the kernel is contained within an NSS. Given that memory savings are minimal if kernel images are shared and in addition updates of shared images are painful, the NSS feature can be removed. Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
| * s390/ctl_reg: use decoding unions in update_cr_regsMartin Schwidefsky2017-10-191-5/+6
| | | | | | | | | | | | | | | | | | | | Add a decoding union for the bits in control registers 2 and use 'union ctlreg0' and 'union ctlreg2' in update_cr_regs to improve readability. Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * s390/kexec: Fix checksum validation return code for kdumpPhilipp Rudo2017-10-181-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Before kexec boots to a crash kernel it checks whether the image in memory changed after load. This is done by the function kdump_csum_valid, which returns true, i.e. an int != 0, on success and 0 otherwise. In other words when kdump_csum_valid returns an error code it means that the validation succeeded. This is not only counterintuitive but also produces the wrong result if the kernel was build without CONFIG_CRASH_DUMP. Fix this by making kdump_csum_valid return a bool. Signed-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com> Acked-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* | License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman2017-11-021-0/+1
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* kexec: move vmcoreinfo out of the kernel's .bss sectionXunlei Pang2017-07-121-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | As Eric said, "what we need to do is move the variable vmcoreinfo_note out of the kernel's .bss section. And modify the code to regenerate and keep this information in something like the control page. Definitely something like this needs a page all to itself, and ideally far away from any other kernel data structures. I clearly was not watching closely the data someone decided to keep this silly thing in the kernel's .bss section." This patch allocates extra pages for these vmcoreinfo_XXX variables, one advantage is that it enhances some safety of vmcoreinfo, because vmcoreinfo now is kept far away from other kernel data structures. Link: http://lkml.kernel.org/r/1493281021-20737-1-git-send-email-xlpang@redhat.com Signed-off-by: Xunlei Pang <xlpang@redhat.com> Tested-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Reviewed-by: Juergen Gross <jgross@suse.com> Suggested-by: Eric Biederman <ebiederm@xmission.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Dave Young <dyoung@redhat.com> Cc: Hari Bathini <hbathini@linux.vnet.ibm.com> Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* s390: use set_memory.h headerLaura Abbott2017-05-081-0/+1
| | | | | | | | | | | set_memory_* functions have moved to set_memory.h. Switch to this explicitly Link: http://lkml.kernel.org/r/1488920133-27229-5-git-send-email-labbott@redhat.com Signed-off-by: Laura Abbott <labbott@redhat.com> Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* s390: add a system call for guarded storageMartin Schwidefsky2017-03-221-1/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds a new system call to enable the use of guarded storage for user space processes. The system call takes two arguments, a command and pointer to a guarded storage control block: s390_guarded_storage(int command, struct gs_cb *gs_cb); The second argument is relevant only for the GS_SET_BC_CB command. The commands in detail: 0 - GS_ENABLE Enable the guarded storage facility for the current task. The initial content of the guarded storage control block will be all zeros. After the enablement the user space code can use load-guarded-storage-controls instruction (LGSC) to load an arbitrary control block. While a task is enabled the kernel will save and restore the current content of the guarded storage registers on context switch. 1 - GS_DISABLE Disables the use of the guarded storage facility for the current task. The kernel will cease to save and restore the content of the guarded storage registers, the task specific content of these registers is lost. 2 - GS_SET_BC_CB Set a broadcast guarded storage control block. This is called per thread and stores a specific guarded storage control block in the task struct of the current task. This control block will be used for the broadcast event GS_BROADCAST. 3 - GS_CLEAR_BC_CB Clears the broadcast guarded storage control block. The guarded- storage control block is removed from the task struct that was established by GS_SET_BC_CB. 4 - GS_BROADCAST Sends a broadcast to all thread siblings of the current task. Every sibling that has established a broadcast guarded storage control block will load this control block and will be enabled for guarded storage. The broadcast guarded storage control block is used up, a second broadcast without a refresh of the stored control block with GS_SET_BC_CB will not have any effect. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/kexec: fix crash on resize of reserved memoryHeiko Carstens2016-06-131-22/+11
| | | | | | | | | | | | | | | Reducing the size of reserved memory for the crash kernel will result in an immediate crash on s390. Reason for that is that we do not create struct pages for memory that is reserved. If that memory is freed any access to struct pages which correspond to this memory will result in invalid memory accesses and a kernel panic. Fix this by properly creating struct pages when the system gets initialized. Change the code also to make use of set_memory_ro() and set_memory_rw() so page tables will be split if required. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/kexec: fix update of os_info crash kernel sizeHeiko Carstens2016-06-131-6/+14
| | | | | | | | | | | | | | | Implement an s390 version of the weak crash_free_reserved_phys_range function. This allows us to update the size of the reserved crash kernel memory if it will be resized. This was previously done with a call to crash_unmap_reserved_pages from crash_shrink_memory which was removed with ("s390/kexec: consolidate crash_map/unmap_reserved_pages() and arch_kexec_protect(unprotect)_crashkres()") Fixes: 7a0058ec7860 ("s390/kexec: consolidate crash_map/unmap_reserved_pages() and arch_kexec_protect(unprotect)_crashkres()") Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/kexec: consolidate crash_map/unmap_reserved_pages() and ↵Xunlei Pang2016-05-231-10/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | arch_kexec_protect(unprotect)_crashkres() Commit 3f625002581b ("kexec: introduce a protection mechanism for the crashkernel reserved memory") is a similar mechanism for protecting the crash kernel reserved memory to previous crash_map/unmap_reserved_pages() implementation, the new one is more generic in name and cleaner in code (besides, some arch may not be allowed to unmap the pgtable). Therefore, this patch consolidates them, and uses the new arch_kexec_protect(unprotect)_crashkres() to replace former crash_map/unmap_reserved_pages() which by now has been only used by S390. The consolidation work needs the crash memory to be mapped initially, this is done in machine_kdump_pm_init() which is after reserve_crashkernel(). Once kdump kernel is loaded, the new arch_kexec_protect_crashkres() implemented for S390 will actually unmap the pgtable like before. Signed-off-by: Xunlei Pang <xlpang@redhat.com> Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Acked-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Minfei Huang <mhuang@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Dave Young <dyoung@redhat.com> Cc: Baoquan He <bhe@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* s390/dump: rework CPU register dump codeMartin Schwidefsky2015-11-271-43/+61
| | | | | | | | | | | | | | | | To collect the CPU registers of the crashed system allocated a single page with memblock_alloc_base and use it as a copy buffer. Replace the stop-and-store-status sigp with a store-status-at-address sigp in smp_save_dump_cpus() and smp_store_status(). In both cases the target CPU is already stopped and store-status-at-address avoids the detour via the absolute zero page. For kexec simplify s390_reset_system and call store_status() before the prefix register of the boot CPU has been set to zero. Use STPX to store the prefix register and remove dump_prefix_page. Acked-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/dump: remove SAVE_AREA_BASEMartin Schwidefsky2015-11-271-3/+3
| | | | | | | | | | | Replace the SAVE_AREA_BASE offset calculations in reipl.S with the assembler constant for the location of each register status area. Use __LC_FPREGS_SAVE_AREA instead of SAVE_AREA_BASE in the three remaining code locations and remove the definition of SAVE_AREA_BASE. Acked-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/kdump: remove code to create ELF notes in the crashed systemMartin Schwidefsky2015-11-271-24/+18
| | | | | | | | | | The s390 architecture can store the CPU registers of the crashed system after the kdump kernel has been started and this is the preferred way. Remove the remaining code fragments that deal with storing CPU registers while the crashed system is still active. Acked-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390: add SMT supportMartin Schwidefsky2015-01-221-11/+8
| | | | | | | | | | | | | | | | | | | | The multi-threading facility is introduced with the z13 processor family. This patch adds code to detect the multi-threading facility. With the facility enabled each core will surface multiple hardware threads to the system. Each hardware threads looks like a normal CPU to the operating system with all its registers and properties. The SCLP interface reports the SMT topology indirectly via the maximum thread id. Each reported CPU in the result of a read-scp-information is a core representing a number of hardware threads. To reflect the reduced CPU capacity if two hardware threads run on a single core the MT utilization counter set is used to normalize the raw cputime obtained by the CPU timer deltas. This scaled cputime is reported via the taskstats interface. The normal /proc/stat numbers are based on the raw cputime and are not affected by the normalization. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/kdump: add support for vector extensionMichael Holzheu2014-10-091-1/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | 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 <heiko.carstens@de.ibm.com> Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390: make various functions static, add declarations to header filesHeiko Carstens2013-09-071-1/+1
| | | | | | | Make various functions static, add declarations to header files to fix a couple of sparse findings. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
* s390/kdump: Add PM notifier for kdumpMichael Holzheu2013-04-151-0/+30
| | | | | | | | | | | | | | | | For s390 the page table mapping for the crashkernel memory is removed to protect the pre-loaded kdump kernel and ramdisk. Because the crashkernel memory is not included in the page tables for suspend/resume it is not included in the suspend image. Therefore after resume the resumed system does no longer contain the pre-loaded kdump kernel and when kdump is triggered it fails. This patch adds a PM notifier that creates the page tables before suspend is done and removes them for resume. This ensures that the kdump kernel is included in the suspend image. Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/crashdump: move fill_cpu_elf_notes() prototype to header fileHeiko Carstens2012-09-261-2/+1
| | | | | | | | | | | Move fill_cpu_elf_notes() prototype to header file. This way we get compile errors if e.g. the number of function parameters get changed. Otherwise it's possible to change just the definition and everything else still compiles fine, but the result is broken code. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/kexec: change return value of machine_kexec_prepareHeiko Carstens2012-09-261-1/+1
| | | | | | | | | | Returning -ENOSYS on kexec_load() is a bad idea since user space cannot tell if the system call is not implmented or if it failed. Use -EOPNOTSUPP in case somebody tries a kexec_load on a NSS image based kernel instead. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/kexec: move machine_crash_shutdown() to machine_kexec.cHeiko Carstens2012-09-261-0/+4
| | | | | | | | machine_crash_shutdown() was the only function in crash.c. So move the function and delete one file. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/comments: unify copyright messages and remove file namesHeiko Carstens2012-07-201-3/+1
| | | | | | | | | | | | | | Remove the file name from the comment at top of many files. In most cases the file name was wrong anyway, so it's rather pointless. Also unify the IBM copyright statement. We did have a lot of sightly different statements and wanted to change them one after another whenever a file gets touched. However that never happened. Instead people start to take the old/"wrong" statements to use as a template for new files. So unify all of them in one go. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
* s390/kdump: Use real mode for PSW restart and kexecMichael Holzheu2012-05-231-1/+2
| | | | | | | | | | | | | | | | | | | | Currently the PSW restart handler and kexec are executed in real mode with DAT=off. For kexec/kdump the function setup_regs() is called that uses the per-cpu variable "crash_notes". Because there are situations when the per-cpu implementation uses vmalloc memory, calling setup_regs() in real mode can cause a program check interrupt. To fix that problem this patch changes the following: * Ensure that diag308_reset() does not change PSW bits to real mode * Enable DAT in __do_restart() after we switched to an online CPU * Enable DAT in __machine_kexec() after we switched to the IPL CPU * Call setup_regs() before we switch to real mode and call purgatory Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/kdump: Account /sys/kernel/kexec_crash_size changes in OS infoMichael Holzheu2012-05-231-1/+7
| | | | | | | | | | | The crashkernel size for kdump can be reduced at runtime with the sysfs file "/sys/kernel/kexec_crash_size". Currently those changes do not update the OS info crashkernel information that is used for stand-alone kdump. With this fix now also the OS info crashkernel information is updated correctly. Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* Disintegrate asm/system.h for S390David Howells2012-03-281-1/+0
| | | | | | | Disintegrate asm/system.h for S390. Signed-off-by: David Howells <dhowells@redhat.com> cc: linux-s390@vger.kernel.org
* [S390] kernel: Add z/VM LGR detectionMichael Holzheu2012-03-111-2/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently the following mechanisms are available to move active Linux on System z instances between machines: * z/VM 6.2 SSI (Single System Image) * Suspend/resume For moving Linux instances in this patch the term LGR (Linux Guest Relocation) is used. Because such an operation is critical, it should be detectable from Linux. With this patch for both, a live system and a kernel dump, the information about LGRs is accessible. To identify a guest, stsi and stfle data is used. A new function lgr_info_log() compares the current data (lgr_info_cur) with the last recorded one (lgr_info_last). In case the two data sets differ, lgr_info_cur is logged to the "lgr" s390dbf. The following trigger points call lgr_info_log(): * panic * die * kdump * LGR timer * PSW restart * QDIO recovery * resume This patch also changes the s390dbf hex_ascii view. Now only printable ASCII characters are shown. Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] rework smp codeMartin Schwidefsky2012-03-111-36/+7
| | | | | | | | | | | | | | | | | | | | | Define struct pcpu and merge some of the NR_CPUS arrays into it, including __cpu_logical_map, current_set and smp_cpu_state. Split smp related functions to those operating on physical cpus and the functions operating on a logical cpu number. Make the functions for physical cpus use a pointer to a struct pcpu. This hides the knowledge about cpu addresses in smp.c, entry[64].S and swsusp_asm64.S, thus remove the sigp.h header. The PSW restart mechanism is used to start secondary cpus, calling a function on an online cpu, calling a function on the ipl cpu, and for the nmi signal. Replace the different assembler functions with a single function restart_int_handler. The new entry point calls a function whose pointer is stored in the lowcore of the target cpu and it can wait for the source cpu to stop. This covers all existing use cases. Overall the code is now simpler and there are ~380 lines less code. Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] Add VMCOREINFO_SYMBOL(high_memory) to vmcoreinfoMichael Holzheu2011-12-271-0/+1
| | | | | | | | | | | Currently the vmalloc_start address (or better end of real memory) for s390x is obtained by makedumpfile using vmlist.addr symbol, which is not correct. The correct vmalloc_start address can be obtained using 'high_memory' symbol. This patch adds the high_memory symbol to vmcoreinfo. Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] cleanup psw related bits and piecesMartin Schwidefsky2011-10-301-1/+1
| | | | | | | | | | Split out addressing mode bits from PSW_BASE_BITS, rename PSW_BASE_BITS to PSW_MASK_BASE, get rid of psw_user32_bits, remove unused function enabled_wait(), introduce PSW_MASK_USER, and drop PSW_MASK_MERGE macros. Change psw_kernel_bits / psw_user_bits to contain only the bits that are always set in the respective mode. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] Add architecture code for unmapping crashkernel memoryMichael Holzheu2011-10-301-0/+31
| | | | | | | | | | | This patch implements the crash_map_pages() function for s390. KEXEC_CRASH_MEM_ALIGN is set to HPAGE_SIZE, in order to support kernel mappings that use large pages. We also use HPAGE_SIZE alignment for CONFIG_HUGETLB_PAGE=n in order to have the same 1 MiB alignment on all s390 systems. Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] kdump backend codeMichael Holzheu2011-10-301-6/+155
| | | | | | | | This patch provides the architecture specific part of the s390 kdump support. Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] kexec: Disable ftrace during kexecHeiko Carstens2011-03-151-0/+2
| | | | | | | | Disable ftrace during kexec. Same as on x86/powerpc. ac4414e "powerpc/kdump: Disable ftrace during kexec". Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] smp: always reboot on cpu 0Heiko Carstens2010-02-261-2/+8
| | | | | | | | | Always reboot on logical cpu 0. This makes sure that the IPL cpu is always the same and usually avoids strange numbering schemes between physical and logical cpus. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] Cleanup kprobes printk messages.Martin Schwidefsky2008-07-141-1/+0
| | | | | Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
* [S390] nss: disable kexec.Heiko Carstens2007-03-051-0/+5
| | | | | | | | nss and kexec don't work together since kexec wants to write to the read-only text section of the shared kernel image. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] Get rid of a lot of sparse warnings.Heiko Carstens2007-02-051-0/+1
| | | | | Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] pfault code cleanup.Heiko Carstens2006-12-041-7/+1
| | | | | Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] cpu shutdown reworkHeiko Carstens2006-12-041-49/+16
| | | | | | | | | Let one master cpu kill all other cpus instead of sending an external interrupt to all other cpus so they can kill themselves. Simplifies reipl/shutdown functions a lot. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] Reset infrastructure for re-IPL.Heiko Carstens2006-12-041-6/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In case of re-IPL and diag308 doesn't work we have to reset all devices manually and wait synchronously that each reset finished. This patch adds the necessary infrastucture and the first exploiter of it. Subsystems that need to add a function that needs to be called at re-IPL may register/unregister this function via struct reset_call { struct reset_call *next; void (*fn)(void); }; void register_reset_call(struct reset_call *reset); void unregister_reset_call(struct reset_call *reset); When the registered function get called the context is: - all cpus beside the current one are stopped - all machine checks and interrupts are disabled - prefixing is disabled - a default machine check handler is available for use The registered functions may not take any locks are sleep. For the common I/O layer part of this patch: Introduce a reset_call css_reset that does the following: - clear all subchannels - perform a rchp on all channel paths and wait for the resulting machine checks This replaces the calls to clear_all_subchannels() and cio_reset_channel_paths() for kexec and ccw reipl. reipl_ccw_dev() now uses reipl_find_schid() to determine the subchannel id for a given device id. Also remove cio_reset_channel_paths() and friends since they are not needed anymore. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] path grouping and path verifications fixes.Cornelia Huck2006-07-121-0/+1
| | | | | | | | | | | | | | | | | | 1. Multipath devices for which SetPGID is not supported are not handled well. Use NOP ccws for path verification (sans path grouping) when SetPGID is not supported. 2. Check for PGIDs already set with SensePGID on _all_ paths (not just the first one) and try to find a common one. Moan if no common PGID can be found (and use NOP verification). If no PGIDs have been set, use the css global PGID (as before). (Rationale: SetPGID will get a command reject if the PGID it tries to set does not match the already set PGID.) 3. Immediately before reboot, issue RESET CHANNEL PATH (rcp) on all chpids. This will remove the old PGIDs. rcp will generate solicited CRWs which can be savely ignored by the machine check handler (all other actions create unsolicited CRWs). Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* Storage class should be firstTobias Klauser2006-06-261-2/+2
| | | | | | | Storage class should be before const Signed-off-by: Tobias Klauser <tklauser@nuerscht.ch> Signed-off-by: Adrian Bunk <bunk@stusta.de>
* [PATCH] s390: fix non smp build of kexecHeiko Carstens2006-02-111-2/+3
| | | | | | | | | Add missing smp_cpu_not_running define to avoid build warnings in the non smp case. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>