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2018-04-05headers: untangle kmemleak.h from mm.hRandy Dunlap1-1/+0
Currently <linux/slab.h> #includes <linux/kmemleak.h> for no obvious reason. It looks like it's only a convenience, so remove kmemleak.h from slab.h and add <linux/kmemleak.h> to any users of kmemleak_* that don't already #include it. Also remove <linux/kmemleak.h> from source files that do not use it. This is tested on i386 allmodconfig and x86_64 allmodconfig. It would be good to run it through the 0day bot for other $ARCHes. I have neither the horsepower nor the storage space for the other $ARCHes. Update: This patch has been extensively build-tested by both the 0day bot & kisskb/ozlabs build farms. Both of them reported 2 build failures for which patches are included here (in v2). [ slab.h is the second most used header file after module.h; kernel.h is right there with slab.h. There could be some minor error in the counting due to some #includes having comments after them and I didn't combine all of those. ] [akpm@linux-foundation.org: security/keys/big_key.c needs vmalloc.h, per sfr] Link: http://lkml.kernel.org/r/e4309f98-3749-93e1-4bb7-d9501a39d015@infradead.org Link: http://kisskb.ellerman.id.au/kisskb/head/13396/ Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Reviewed-by: Ingo Molnar <mingo@kernel.org> Reported-by: Michael Ellerman <mpe@ellerman.id.au> [2 build failures] Reported-by: Fengguang Wu <fengguang.wu@intel.com> [2 build failures] Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Wei Yongjun <weiyongjun1@huawei.com> Cc: Luis R. Rodriguez <mcgrof@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: John Johansen <john.johansen@canonical.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-07s390: introduce execute-trampolines for branchesMartin Schwidefsky1-0/+1
Add CONFIG_EXPOLINE to enable the use of the new -mindirect-branch= and -mfunction_return= compiler options to create a kernel fortified against the specte v2 attack. With CONFIG_EXPOLINE=y all indirect branches will be issued with an execute type instruction. For z10 or newer the EXRL instruction will be used, for older machines the EX instruction. The typical indirect call basr %r14,%r1 is replaced with a PC relative call to a new thunk brasl %r14,__s390x_indirect_jump_r1 The thunk contains the EXRL/EX instruction to the indirect branch __s390x_indirect_jump_r1: exrl 0,0f j . 0: br %r1 The detour via the execute type instruction has a performance impact. To get rid of the detour the new kernel parameter "nospectre_v2" and "spectre_v2=[on,off,auto]" can be used. If the parameter is specified the kernel and module code will be patched at runtime. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-02-05s390: add options to change branch prediction behaviour for the kernelMartin Schwidefsky1-0/+2
Add the PPA instruction to the system entry and exit path to switch the kernel to a different branch prediction behaviour. The instructions are added via CPU alternatives and can be disabled with the "nospec" or the "nobp=0" kernel parameter. If the default behaviour selected with CONFIG_KERNEL_NOBP is set to "n" then the "nobp=1" parameter can be used to enable the changed kernel branch prediction. Acked-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-02-05s390/alternative: use a copy of the facility bit maskMartin Schwidefsky1-1/+3
To be able to switch off specific CPU alternatives with kernel parameters make a copy of the facility bit mask provided by STFLE and use the copy for the decision to apply an alternative. Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-01-09treewide: Use DEVICE_ATTR_WOJoe Perches1-1/+1
Convert DEVICE_ATTR uses to DEVICE_ATTR_WO where possible. Done with perl script: $ git grep -w --name-only DEVICE_ATTR | \ xargs perl -i -e 'local $/; while (<>) { s/\bDEVICE_ATTR\s*\(\s*(\w+)\s*,\s*\(?(?:\s*S_IWUSR\s*|\s*0200\s*)\)?\s*,\s*NULL\s*,\s*\s_store\s*\)/DEVICE_ATTR_WO(\1)/g; print;}' Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-20s390/topology: fix compile error in file arch/s390/kernel/smp.cThomas Richter1-0/+1
Commit 1887aa07b676 ("s390/topology: add detection of dedicated vs shared CPUs") introduced following compiler error when CONFIG_SCHED_TOPOLOGY is not set. CC arch/s390/kernel/smp.o ... arch/s390/kernel/smp.c: In function ‘smp_start_secondary’: arch/s390/kernel/smp.c:812:6: error: implicit declaration of function ‘topology_cpu_dedicated’; did you mean ‘topology_cpu_init’? This patch fixes the compiler error by adding function topology_cpu_dedicated() to return false when this config option is not defined. Signed-off-by: Thomas Richter <tmricht@linux.vnet.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-11-13Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linuxLinus Torvalds1-51/+36
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 ...
2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman1-0/+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>
2017-10-19s390/nmi: allocation of the extended save areaMartin Schwidefsky1-36/+7
The machine check extended save area is needed to store the vector registers and the guarded storage control block when a CPU is interrupted by a machine check. Move the slab cache allocation of the full save area to nmi.c, for early boot use a static __initdata block. Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-10-19s390/nmi: use smp_emergency_stop instead of smp_send_stopMartin Schwidefsky1-13/+17
The smp_send_stop() function can be called from s390_handle_damage while DAT is off. This happens if a machine check indicates that kernel gprs or control registers can not be restored. The function smp_send_stop reenables DAT via __load_psw_mask. That should work for the case of lost kernel gprs and the system will do the expected stop of all CPUs. But if control registers are lost, in particular CR13 with the home space ASCE, interesting secondary crashes may occur. Make smp_emergency_stop callable from nmi.c and remove the cpumask argument. Replace the smp_send_stop call with smp_emergency_stop in the s390_handle_damage function. In addition add notrace and NOKPROBE_SYMBOL annotations for all functions required for the emergency shutdown. Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-10-16s390/cputime: fix guest/irq/softirq times after CPU hotplugChristian Borntraeger1-0/+3
On CPU hotplug some cpu stats contain bogus values: $ cat /proc/stat cpu 0 0 49 1280 0 0 0 3 0 0 cpu0 0 0 49 618 0 0 0 3 0 0 cpu1 0 0 0 662 0 0 0 0 0 0 [...] $ echo 0 > /sys/devices/system/cpu/cpu1/online $ echo 1 > /sys/devices/system/cpu/cpu1/online $ cat /proc/stat cpu 0 0 49 3200 0 450359962737 450359962737 3 0 0 cpu0 0 0 49 1956 0 0 0 3 0 0 cpu1 0 0 0 1244 0 450359962737 450359962737 0 0 0 [...] pcpu_attach_task() needs the same assignments as vtime_task_switch. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Fixes: b7394a5f4ce9 ("sched/cputime, s390: Implement delayed accounting of system time") Cc: stable@vger.kernel.org # 4.11+ Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-09-28s390/spinlock: introduce spinlock wait queueingMartin Schwidefsky1-0/+4
The queued spinlock code for s390 follows the principles of the common code qspinlock implementation but with a few notable differences. The format of the spinlock_t locking word differs, s390 needs to store the logical CPU number of the lock holder in the spinlock_t to be able to use the diagnose 9c directed yield hypervisor call. The inline code sequences for spin_lock and spin_unlock are nice and short. The inline portion of a spin_lock now typically looks like this: lhi %r0,0 # 0 indicates an empty lock l %r1,0x3a0 # CPU number + 1 from lowcore cs %r0,%r1,<some_lock> # lock operation jnz call_wait # on failure call wait function locked: ... call_wait: la %r2,<some_lock> brasl %r14,arch_spin_lock_wait j locked A spin_unlock is as simple as before: lhi %r0,0 sth %r0,2(%r2) # unlock operation After a CPU has queued itself it may not enable interrupts again for the arch_spin_lock_flags() variant. The arch_spin_lock_wait_flags wait function is removed. To improve performance the code implements opportunistic lock stealing. If the wait function finds a spinlock_t that indicates that the lock is free but there are queued waiters, the CPU may steal the lock up to three times without queueing itself. The lock stealing update the steal counter in the lock word to prevent more than 3 steals. The counter is reset at the time the CPU next in the queue successfully takes the lock. While the queued spinlocks improve performance in a system with dedicated CPUs, in a virtualized environment with continuously overcommitted CPUs the queued spinlocks can have a negative effect on performance. This is due to the fact that a queued CPU that is preempted by the hypervisor will block the queue at some point even without holding the lock. With the classic spinlock it does not matter if a CPU is preempted that waits for the lock. Therefore use the queued spinlock code only if the system runs with dedicated CPUs and fall back to classic spinlocks when running with shared CPUs. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-09-28s390/topology: add detection of dedicated vs shared CPUsMartin Schwidefsky1-2/+8
The topology information returned by STSI 15.x.x contains a flag if the CPUs of a topology-list are dedicated or shared. Make this information available if the machine provides topology information. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-08-23s390/smp: convert cpuhp_setup_state() return code to zero on successHeiko Carstens1-0/+1
cpuhp_setup_state() returns a state number on CPUHP_AP_ONLINE_DYN if no error occurred. Therefore convert the return code to zero before using it as exit code for s390_smp_init(). Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-06-12s390/smp: fix false positive kmemleak of mcesa data structureChristian Borntraeger1-0/+3
I get number of CPUs - 1 kmemleak hits like unreferenced object 0x37ec6f000 (size 1024): comm "swapper/0", pid 1, jiffies 4294937330 (age 889.690s) hex dump (first 32 bytes): 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk backtrace: [<000000000034a848>] kmem_cache_alloc+0x2b8/0x3d0 [<00000000001164de>] __cpu_up+0x456/0x488 [<000000000016f60c>] bringup_cpu+0x4c/0xd0 [<000000000016d5d2>] cpuhp_invoke_callback+0xe2/0x9e8 [<000000000016f3c6>] cpuhp_up_callbacks+0x5e/0x110 [<000000000016f988>] _cpu_up+0xe0/0x158 [<000000000016faf0>] do_cpu_up+0xf0/0x110 [<0000000000dae1ee>] smp_init+0x126/0x130 [<0000000000d9bd04>] kernel_init_freeable+0x174/0x2e0 [<000000000089fc62>] kernel_init+0x2a/0x148 [<00000000008adce2>] kernel_thread_starter+0x6/0xc [<00000000008adcdc>] kernel_thread_starter+0x0/0xc [<ffffffffffffffff>] 0xffffffffffffffff The pointer of this data structure is stored in the prefix page of that CPU together with some extra bits ORed into the the low bits. Mark the data structure as non-leak. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-03-22Merge branch 'guarded-storage' into 'features' to make merging withMartin Schwidefsky1-5/+38
the KVM tree easier.
2017-03-22s390/smp: fix ipl from cpu with non-zero addressHeiko Carstens1-3/+2
Commit af51160ebd3c ("s390/smp: initialize cpu_present_mask in setup_arch") initializes the cpu_present_mask much earlier than before. However the cpu detection code relies on the fact that iff logical cpu 0 is marked present then also the corresponding physical cpu address within the pcpu_devices array slot is valid. Since commit 44fd22992cb7 ("[PATCH] Register the boot-cpu in the cpu maps earlier") this assumption is not true anymore. The patch marks logical cpu 0 as present in common code without that architecture code had a chance to setup the logical to physical map. With that change the cpu detection code assumes that the physical cpu address of cpu 0 is also 0, which is not necessarily true. Subsequently the physical cpu address of the ipl cpu will be mapped to a different logical cpu. If that cpu is brought online later the ipl cpu will send itself an initial cpu reset sigp signal. This in turn completely resets the ipl cpu and the system stops working. A dump of such a system looks like a "store status" has been forgotten. But actually the kernel itself removed all traces which would allow to easily tell what went wrong. To fix this initialize the logical to physical cpu address already in smp_setup_processor_id(). In addition remove the initialization of the cpu_present_mask and cpu_online_mask for cpu 0, since that has already been done. Also add a sanity check, just in case common code will be changed again... The problem can be easily reproduced within a z/VM guest: > chcpu -d 0 > vmcp ipl Fixes: af51160ebd3c ("s390/smp: initialize cpu_present_mask in setup_arch") Reported-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-03-22s390: add a system call for guarded storageMartin Schwidefsky1-5/+38
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>
2017-03-02sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task_stack.h>Ingo Molnar1-0/+1
We are going to split <linux/sched/task_stack.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/task_stack.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02sched/headers: Prepare for new header dependencies before moving code to <linux/sched/hotplug.h>Ingo Molnar1-0/+1
We are going to split <linux/sched/hotplug.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/hotplug.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-02-17s390: kernel: Audit and remove any unnecessary uses of module.hPaul Gortmaker1-1/+1
Historically a lot of these existed because we did not have a distinction between what was modular code and what was providing support to modules via EXPORT_SYMBOL and friends. That changed when we forked out support for the latter into the export.h file. This means we should be able to reduce the usage of module.h in code that is obj-y Makefile or bool Kconfig. The advantage in doing so is that module.h itself sources about 15 other headers; adding significantly to what we feed cpp, and it can obscure what headers we are effectively using. Since module.h was the source for init.h (for __init) and for export.h (for EXPORT_SYMBOL) we consider each change instance for the presence of either and replace as needed. Build testing revealed some implicit header usage that was fixed up accordingly. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-12-13Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linuxLinus Torvalds1-19/+13
Pull s390 updates from Martin Schwidefsky: "The main bulk of the s390 patches for the 4.10 merge window: - Add support for the contiguous memory allocator. - The recovery for I/O errors in the dasd device driver is improved, the driver will now remove channel paths that are not working properly. - Additional fields are added to /proc/sysinfo, the extended partition name and the partition UUID. - New naming for PCI devices with system defined UIDs. - The last few remaining alloc_bootmem calls are converted to memblock. - The thread_info structure is stripped down and moved to the task_struct. The only field left in thread_info is the flags field. - Rework of the arch topology code to fix a fake numa issue. - Refactoring of the atomic primitives and add a new preempt_count implementation. - Clocksource steering for the STP sync check offsets. - The s390 specific headers are changed to make them usable with CLANG. - Bug fixes and cleanup" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (70 commits) s390/cpumf: Use configuration level indication for sampling data s390: provide memmove implementation s390: cleanup arch/s390/kernel Makefile s390: fix initrd corruptions with gcov/kcov instrumented kernels s390: exclude early C code from gcov profiling s390/dasd: channel path aware error recovery s390/dasd: extend dasd path handling s390: remove unused labels from entry.S s390/vmlogrdr: fix IUCV buffer allocation s390/crypto: unlock on error in prng_tdes_read() s390/sysinfo: show partition extended name and UUID if available s390/numa: pin all possible cpus to nodes early s390/numa: establish cpu to node mapping early s390/topology: use cpu_topology array instead of per cpu variable s390/smp: initialize cpu_present_mask in setup_arch s390/topology: always use s390 specific sched_domain_topology_level s390/smp: use smp_get_base_cpu() helper function s390/numa: always use logical cpu and core ids s390: Remove VLAIS in ptff() and clear_table() s390: fix machine check panic stack switch ...
2016-12-12Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-25/+11
Pull smp hotplug updates from Thomas Gleixner: "This is the final round of converting the notifier mess to the state machine. The removal of the notifiers and the related infrastructure will happen around rc1, as there are conversions outstanding in other trees. The whole exercise removed about 2000 lines of code in total and in course of the conversion several dozen bugs got fixed. The new mechanism allows to test almost every hotplug step standalone, so usage sites can exercise all transitions extensively. There is more room for improvement, like integrating all the pointlessly different architecture mechanisms of synchronizing, setting cpus online etc into the core code" * 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (60 commits) tracing/rb: Init the CPU mask on allocation soc/fsl/qbman: Convert to hotplug state machine soc/fsl/qbman: Convert to hotplug state machine zram: Convert to hotplug state machine KVM/PPC/Book3S HV: Convert to hotplug state machine arm64/cpuinfo: Convert to hotplug state machine arm64/cpuinfo: Make hotplug notifier symmetric mm/compaction: Convert to hotplug state machine iommu/vt-d: Convert to hotplug state machine mm/zswap: Convert pool to hotplug state machine mm/zswap: Convert dst-mem to hotplug state machine mm/zsmalloc: Convert to hotplug state machine mm/vmstat: Convert to hotplug state machine mm/vmstat: Avoid on each online CPU loops mm/vmstat: Drop get_online_cpus() from init_cpu_node_state/vmstat_cpu_dead() tracing/rb: Convert to hotplug state machine oprofile/nmi timer: Convert to hotplug state machine net/iucv: Use explicit clean up labels in iucv_init() x86/pci/amd-bus: Convert to hotplug state machine x86/oprofile/nmi: Convert to hotplug state machine ...
2016-12-07s390/smp: initialize cpu_present_mask in setup_archHeiko Carstens1-13/+9
In order to be able to setup the cpu to node mappings early it is a prerequisite to know which cpus are present. Therefore cpus must be detected much earlier than before. For sclp based cpu detection this requires yet another early sclp call, since the system is not ready to use the regular interrupt and memory allocations. Reviewed-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-12-07s390/smp: use smp_get_base_cpu() helper functionHeiko Carstens1-2/+2
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-11-22locking/spinlocks, s390: Implement vcpu_is_preempted(cpu)Christian Borntraeger1-2/+7
This implements the s390 version for vcpu_is_preempted(cpu), by reworking the existing smp_vcpu_scheduled() function into arch_vcpu_is_preempted(). We can then also get rid of the local cpu_is_preempted() function by moving the CIF_ENABLED_WAIT test into arch_vcpu_is_preempted(). Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: David.Laight@ACULAB.COM Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: benh@kernel.crashing.org Cc: boqun.feng@gmail.com Cc: bsingharora@gmail.com Cc: dave@stgolabs.net Cc: jgross@suse.com Cc: kernellwp@gmail.com Cc: konrad.wilk@oracle.com Cc: linuxppc-dev@lists.ozlabs.org Cc: mpe@ellerman.id.au Cc: paulmck@linux.vnet.ibm.com Cc: paulus@samba.org Cc: pbonzini@redhat.com Cc: rkrcmar@redhat.com Cc: virtualization@lists.linux-foundation.org Cc: will.deacon@arm.com Cc: xen-devel-request@lists.xenproject.org Cc: xen-devel@lists.xenproject.org Link: http://lkml.kernel.org/r/1478077718-37424-6-git-send-email-xinhui.pan@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-11s390: move cputime accounting fields from thread_info to thread_structMartin Schwidefsky1-3/+2
The user_timer and system_timer fields are used for the per-thread cputime accounting code. The access to these values is simpler if they are moved to the thread_struct as the task_thread_info(tsk) indirection is not needed anymore. Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-11-11s390: move thread_info into task_structHeiko Carstens1-1/+0
This is the s390 variant of commit 15f4eae70d36 ("x86: Move thread_info into task_struct"). Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-11-09s390/smp: Convert to hotplug state machineSebastian Andrzej Siewior1-26/+11
cpuhp_setup_state() invokes the startup callback on all online cpus with the proper protection, so we can remove the cpu hotplug protection from the init function and the creation of the per cpu files for online cpus in smp_add_present_cpu(). smp_add_present_cpu() is called also called from __smp_rescan_cpus(), but this callpath never adds an online cpu, it merily adds newly present cpus, so the creation of the cpu files is not required. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: linux-s390@vger.kernel.org Cc: rt@linutronix.de Link: http://lkml.kernel.org/r/20161104144502.7kd4bxz2rxqvtack@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-11-09s390/smp: Make cpu notifier symetricThomas Gleixner1-1/+2
There is no reason to remove the sysfs cpu files when the CPU is dead, they can be removed when the cpu is prepared to go down. Doing it at DOWN_PREPARE allows us to convert it to a symetric hotplug state in the next step. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: linux-s390@vger.kernel.org Cc: rt@linutronix.de Link: http://lkml.kernel.org/r/20161104144140.lcee6kwmwlx37m7g@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-07-18s390/smp: clean up a conditionDan Carpenter1-1/+1
I can never remember precedence rules. Let's add some parenthesis so this code is more clear. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-06-28s390/smp: use basic blocks for sigp inline assembliesHeiko Carstens1-7/+1
Use only simple inline assemblies which consist of a single basic block if the register asm construct is being used. Otherwise gcc would generate broken code if the compiler option --sanitize-coverage=trace-pc would be used. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-06-13s390/mm: simplify the TLB flushing codeMartin Schwidefsky1-6/+2
ptep_flush_lazy and pmdp_flush_lazy use mm->context.attach_count to decide between a lazy TLB flush vs an immediate TLB flush. The field contains two 16-bit counters, the number of CPUs that have the mm attached and can create TLB entries for it and the number of CPUs in the middle of a page table update. The __tlb_flush_asce, ptep_flush_direct and pmdp_flush_direct functions use the attach counter and a mask check with mm_cpumask(mm) to decide between a local flush local of the current CPU and a global flush. For all these functions the decision between lazy vs immediate and local vs global TLB flush can be based on CPU masks. There are two masks: the mm->context.cpu_attach_mask with the CPUs that are actively using the mm, and the mm_cpumask(mm) with the CPUs that have used the mm since the last full flush. The decision between lazy vs immediate flush is based on the mm->context.cpu_attach_mask, to decide between local vs global flush the mm_cpumask(mm) is used. With this patch all checks will use the CPU masks, the old counter mm->context.attach_count with its two 16-bit values is turned into a single counter mm->context.flush_count that keeps track of the number of CPUs with incomplete page table updates. The sole user of this counter is finish_arch_post_lock_switch() which waits for the end of all page table updates. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-05-06sched: Allow per-cpu kernel threads to run on online && !activePeter Zijlstra (Intel)1-1/+1
In order to enable symmetric hotplug, we must mirror the online && !active state of cpu-down on the cpu-up side. However, to retain sanity, limit this state to per-cpu kthreads. Aside from the change to set_cpus_allowed_ptr(), which allow moving the per-cpu kthreads on, the other critical piece is the cpu selection for pinned tasks in select_task_rq(). This avoids dropping into select_fallback_rq(). select_fallback_rq() cannot be allowed to select !active cpus because its used to migrate user tasks away. And we do not want to move user tasks onto cpus that are in transition. Requested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Thomas Gleixner <tglx@linutronix.de> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Jan H. Schönherr <jschoenh@amazon.de> Cc: Oleg Nesterov <oleg@redhat.com> Cc: rt@linutronix.de Link: http://lkml.kernel.org/r/20160301152303.GV6356@twins.programming.kicks-ass.net Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-03-01arch/hotplug: Call into idle with a proper stateThomas Gleixner1-1/+1
Let the non boot cpus call into idle with the corresponding hotplug state, so the hotplug core can handle the further bringup. That's a first step to convert the boot side of the hotplugged cpus to do all the synchronization with the other side through the state machine. For now it'll only start the hotplug thread and kick the full bringup of the cpu. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: linux-arch@vger.kernel.org Cc: Rik van Riel <riel@redhat.com> Cc: Rafael Wysocki <rafael.j.wysocki@intel.com> Cc: "Srivatsa S. Bhat" <srivatsa@mit.edu> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Sebastian Siewior <bigeasy@linutronix.de> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Paul McKenney <paulmck@linux.vnet.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul Turner <pjt@google.com> Link: http://lkml.kernel.org/r/20160226182341.614102639@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-01-19s390: remove superfluous memblock_alloc() return value checksHeiko Carstens1-2/+0
memblock_alloc() and memblock_alloc_base() will panic on their own if they can't find free memory. Therefore remove some pointless checks. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Acked-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-01-11s390: rename struct _lowcore to struct lowcoreHeiko Carstens1-8/+8
Finally get rid of the leading underscore. I tried this already two or three years ago, however Michael Holzheu objected since this would break the crash utility (again). However Michael integrated support for the new name into the crash utility back then, so it doesn't break if the name will be changed now. So finally get rid of the ever confusing leading underscore. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-12-18s390/smp: save timestamp on external callsHeiko Carstens1-0/+2
This is supposed to make debugging easier: if within a dump we can see that an external call or emergency signal IPI is pending but all cpus are idle, we have no idea for how long the interrupt is outstanding. Therefore save a timestamp into the per cpu pcpu array of the target cpu whenever such an IPI is sent. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-27s390/dump: cleanup CPU save area handlingMartin Schwidefsky1-23/+14
Introduce save_area_alloc(), save_area_boot_cpu(), save_area_add_regs() and save_area_add_vxrs to deal with storing the CPU state in case of a system dump. Remove struct save_area and save_area_ext, and create a new struct save_area as a local definition to arch/s390/kernel/crash_dump.c. Copy each individual field from the hardware status area to the save area, storing the minimum of required data. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-27s390/dump: rework CPU register dump codeMartin Schwidefsky1-51/+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>
2015-11-27s390/dump: remove SAVE_AREA_BASEMartin Schwidefsky1-2/+2
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>
2015-11-27s390/dump: streamline oldmem copy functionsMartin Schwidefsky1-2/+2
Introduce two copy functions for the memory of the dumped system, copy_oldmem_kernel() to copy to the virtual kernel address space and copy_oldmem_user() to copy to user space. Acked-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-27s390/kdump: remove code to create ELF notes in the crashed systemMartin Schwidefsky1-6/+2
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>
2015-10-14s390/cpumf: rework program parameter setting to detect guest samplesChristian Borntraeger1-0/+2
The program parameter can be used to mark hardware samples with some token. Previously, it was used to mark guest samples only. Improve the program parameter doubleword by combining two parts, the leftmost LPP part and the rightmost PID part. Set the PID part for processes by using the task PID. To distinguish host and guest samples for the kernel (PID part is zero), the guest must always set the program paramater to a non-zero value. Use the leftmost bit in the LPP part of the program parameter to be able to detect guest kernel samples. [brueckner@linux.vnet.ibm.com]: Split __LC_CURRENT and introduced __LC_LPP. Corrected __LC_CURRENT users and adjusted assembler parts. And updated the commit message accordingly. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14s390/diag: add tracepoint for diagnose callsMartin Schwidefsky1-2/+2
To be able to analyse problems in regard to hypervisor overhead add a tracepoing for diagnose calls. It reports the number of the diagnose issued, e.g. sshd-1385 [002] .... 42.701431: diagnose: nr=0x9c <idle>-0 [001] ..s. 43.587528: diagnose: nr=0x9c Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14s390/diag: add a statistic for diagnose callsMartin Schwidefsky1-2/+6
Introduce /sys/debug/kernel/diag_stat with a statistic how many diagnose calls have been done by each CPU in the system. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-07-29s390/smp: add missing __init annotation to __smp_store_cpu_state()Heiko Carstens1-2/+2
Section mismatch in reference from the function __smp_store_cpu_state() to the function .init.text:memblock_alloc() The function __smp_store_cpu_state() references the function __init memblock_alloc(). Reviewed-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-06-29s390/kdump: fix compile for !SMPHeiko Carstens1-23/+21
Fix this compile error: arch/s390/kernel/setup.c:875:2: error: implicit declaration of function 'smp_save_dump_cpus' Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-06-25s390/kdump: fix nosmt kernel parameterMichael Holzheu1-30/+40
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 <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-06-25s390/smp: cleanup core vs. cpu in the SCLP interfaceMartin Schwidefsky1-24/+25
The SCLP interface to query, configure and deconfigure CPUs actually operates on cores. For a machine without the multi-threading faciltiy a CPU and a core are equivalent but starting with System z13 a core can have multiple hardware threads, also referred to as logical CPUs. To avoid confusion replace the word 'cpu' with 'core' in the SCLP interface. Also replace MAX_CPU_ADDRESS with SCLP_MAX_CORES. The core-id is an 8-bit field, the maximum thread id is in the range 0-31. The theoretical limit for the CPU address is therefore 8191. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>