kernel.git/arch/s390/kernel/ftrace.c, branch linux-5.18.y

s390: convert ".insn" encoding to instruction names

2022-03-10T14:58:17Z

With z10 as minimum supported machine generation many ".insn" encodings could be now converted to instruction names. There are couple of exceptions - stfle is used from the als code built for z900 and cannot be converted - few ".insn" directives encode unsupported instruction formats The generated code is identical before/after this change. Acked-by: Ilya Leoshkevich Reviewed-by: Heiko Carstens Signed-off-by: Vasily Gorbik

s390: raise minimum supported machine generation to z10

2022-03-10T14:58:17Z

Machine generations up to z9 (released in May 2006) have been officially out of service for several years now (z9 end of service - January 31, 2019). No distributions build kernels supporting those old machine generations anymore, except Debian, which seems to pick the oldest supported generation. The team supporting Debian on s390 has been notified about the change. Raising minimum supported machine generation to z10 helps to reduce maintenance cost and effectively remove code, which is not getting enough testing coverage due to lack of older hardware and distributions support. Besides that this unblocks some optimization opportunities and allows to use wider instruction set in asm files for future features implementation. Due to this change spectre mitigation and usercopy implementations could be drastically simplified and many newer instructions could be converted from ".insn" encoding to instruction names. Acked-by: Ilya Leoshkevich Reviewed-by: Heiko Carstens Signed-off-by: Vasily Gorbik

Merge branch 'fixes' into features

2022-03-01T20:02:48Z

This helps to avoid several merge conflicts later. * fixes: s390/extable: fix exception table sorting s390/ftrace: fix arch_ftrace_get_regs implementation s390/ftrace: fix ftrace_caller/ftrace_regs_caller generation s390/setup: preserve memory at OLDMEM_BASE and OLDMEM_SIZE s390/cio: verify the driver availability for path_event call s390/module: fix building test_modules_helpers.o with clang MAINTAINERS: downgrade myself to Reviewer for s390 MAINTAINERS: add Alexander Gordeev as maintainer for s390 Signed-off-by: Vasily Gorbik

s390/ftrace: fix arch_ftrace_get_regs implementation

2022-03-01T19:41:28Z

arch_ftrace_get_regs is supposed to return a struct pt_regs pointer only if the pt_regs structure contains all register contents, which means it must have been populated when created via ftrace_regs_caller. If it was populated via ftrace_caller the contents are not complete (the psw mask part is missing), and therefore a NULL pointer needs be returned. The current code incorrectly always returns a struct pt_regs pointer. Fix this by adding another pt_regs flag which indicates if the contents are complete, and fix arch_ftrace_get_regs accordingly. Fixes: 894979689d3a ("s390/ftrace: provide separate ftrace_caller/ftrace_regs_caller implementations") Reported-by: Christophe Leroy Reported-by: Naveen N. Rao Reviewed-by: Sven Schnelle Acked-by: Ilya Leoshkevich Signed-off-by: Heiko Carstens Signed-off-by: Vasily Gorbik

s390/ftrace: fix ftrace_caller/ftrace_regs_caller generation

2022-03-01T19:41:28Z

ftrace_caller was used for both ftrace_caller and ftrace_regs_caller, which means that the target address of the hotpatch trampoline was never updated. With commit 894979689d3a ("s390/ftrace: provide separate ftrace_caller/ftrace_regs_caller implementations") a separate ftrace_regs_caller entry point was implemeted, however it was forgotten to implement the necessary changes for ftrace_modify_call and ftrace_make_call, where the branch target has to be modified accordingly. Therefore add the missing code now. Fixes: 894979689d3a ("s390/ftrace: provide separate ftrace_caller/ftrace_regs_caller implementations") Reviewed-by: Sven Schnelle Acked-by: Ilya Leoshkevich Signed-off-by: Heiko Carstens Signed-off-by: Vasily Gorbik

s390/ftrace: verify opcode before applying patch

2022-02-06T22:31:29Z

commit 72b3942a173c ("scripts: ftrace - move the sort-processing in ftrace_init") had the unexpected side effect that wrong code locations were patched. To prevent this from happening again, verify the opcode before patching it. Signed-off-by: Sven Schnelle Reviewed-by: Heiko Carstens Signed-off-by: Vasily Gorbik

s390: remove invalid email address of Heiko Carstens

2022-02-06T22:31:29Z

Remove my old invalid email address which can be found in a couple of files. Instead of updating it, just remove my contact data completely from source files. We have git and other tools which allow to figure out who is responsible for what with recent contact data. Signed-off-by: Heiko Carstens Signed-off-by: Vasily Gorbik

s390/ftrace: remove preempt_disable()/preempt_enable() pair

2021-12-10T15:12:34Z

It looks like commit ce5e48036c9e76a2 ("ftrace: disable preemption when recursion locked") missed a spot in kprobe_ftrace_handler() in arch/s390/kernel/ftrace.c. Remove the superfluous preempt_disable/enable_notrace() there too. Fixes: ce5e48036c9e76a2 ("ftrace: disable preemption when recursion locked") Signed-off-by: Jerome Marchand Link: https://lore.kernel.org/r/20211208151503.1510381-1-jmarchan@redhat.com Signed-off-by: Heiko Carstens

Merge tag 's390-5.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

2021-11-06T21:48:06Z

Pull s390 updates from Vasily Gorbik: - Add support for ftrace with direct call and ftrace direct call samples. - Add support for kernel command lines longer than current 896 bytes and make its length configurable. - Add support for BEAR enhancement facility to improve last breaking event instruction tracking. - Add kprobes sanity checks and testcases to prevent kprobe in the mid of an instruction. - Allow concurrent access to /dev/hwc for the CPUMF users. - Various ftrace / jump label improvements. - Convert unwinder tests to KUnit. - Add s390_iommu_aperture kernel parameter to tweak the limits on concurrently usable DMA mappings. - Add ap.useirq AP module option which can be used to disable interrupt use. - Add add_disk() error handling support to block device drivers. - Drop arch specific and use generic implementation of strlcpy and strrchr. - Several __pa/__va usages fixes. - Various cio, crypto, pci, kernel doc and other small fixes and improvements all over the code. [ Merge fixup as per https://lore.kernel.org/all/YXAqZ%2FEszRisunQw@osiris/ ] * tag 's390-5.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (63 commits) s390: make command line configurable s390: support command lines longer than 896 bytes s390/kexec_file: move kernel image size check s390/pci: add s390_iommu_aperture kernel parameter s390/spinlock: remove incorrect kernel doc indicator s390/string: use generic strlcpy s390/string: use generic strrchr s390/ap: function rework based on compiler warning s390/cio: make ccw_device_dma_* more robust s390/vfio-ap: s390/crypto: fix all kernel-doc warnings s390/hmcdrv: fix kernel doc comments s390/ap: new module option ap.useirq s390/cpumf: Allow multiple processes to access /dev/hwc s390/bitops: return true/false (not 1/0) from bool functions s390: add support for BEAR enhancement facility s390: introduce nospec_uses_trampoline() s390: rename last_break to pgm_last_break s390/ptrace: add last_break member to pt_regs s390/sclp: sort out physical vs virtual pointers usage s390/setup: convert start and end initrd pointers to virtual ...

s390/ftrace: add missing serialization for graph caller patching

2021-10-11T18:55:58Z

CPUs must be serialized also when ftrace_graph_caller gets patched. This is missing since ftrace function graph support was added on s390. Signed-off-by: Heiko Carstens Signed-off-by: Vasily Gorbik