BMC/Intel-BMC/linux.git/arch/s390/kernel, branch dev-5.8

s390/ptrace: fix storage key handling

2020-08-26T09:49:12+00:00

[ Upstream commit fd78c59446b8d050ecf3e0897c5a486c7de7c595 ] The key member of the runtime instrumentation control block contains only the access key, not the complete storage key. Therefore the value must be shifted by four bits. Since existing user space does not necessarily query and set the access key correctly, just ignore the user space provided key and use the correct one. Note: this is only relevant for debugging purposes in case somebody compiles a kernel with a default storage access key set to a value not equal to zero. Fixes: 262832bc5acd ("s390/ptrace: add runtime instrumention register get/set") Reported-by: Claudio Imbrenda Signed-off-by: Heiko Carstens Signed-off-by: Sasha Levin

s390/runtime_instrumentation: fix storage key handling

2020-08-26T09:49:12+00:00

[ Upstream commit 9eaba29c7985236e16468f4e6a49cc18cf01443e ] The key member of the runtime instrumentation control block contains only the access key, not the complete storage key. Therefore the value must be shifted by four bits. Note: this is only relevant for debugging purposes in case somebody compiles a kernel with a default storage access key set to a value not equal to zero. Fixes: e4b8b3f33fca ("s390: add support for runtime instrumentation") Reported-by: Claudio Imbrenda Signed-off-by: Heiko Carstens Signed-off-by: Sasha Levin

s390/cpum_cf,perf: change DFLT_CCERROR counter name

2020-07-21T11:53:56+00:00

Change the counter name DLFT_CCERROR to DLFT_CCFINISH on IBM z15. This counter counts completed DEFLATE instructions with exit code 0, 1 or 2. Since exit code 0 means success and exit code 1 or 2 indicate errors, change the counter name to avoid confusion. This counter is incremented each time the DEFLATE instruction completed regardless if an error was detected or not. Fixes: d68d5d51dc89 ("s390/cpum_cf: Add new extended counters for IBM z15") Fixes: e7950166e402 ("perf vendor events s390: Add new deflate counters for IBM z15") Cc: stable@vger.kernel.org # v5.7 Signed-off-by: Thomas Richter Reviewed-by: Sumanth Korikkar Signed-off-by: Heiko Carstens

s390/cpum_sf: prohibit callchain data collection

2020-07-01T18:02:33+00:00

CPU Measurement sampling facility on s390 does not support perf tool collection of callchain data using --call-graph option. The sampling facility collects samples in a ring buffer which includes only the instruction address the samples were taken. When the ring buffer hits a watermark, a measurement alert interrupt is triggered and handled by the performance measurement unit (PMU) device driver. It collects the samples and feeds each sample to the perf ring buffer in the common code via functions perf_prepare_sample()/perf_output_sample(). When function perf_prepare_sample() is called to collect sample data's callchain, user register values or stack area, invalid data is picked, because the context of the collected information does not match the context when the sample was taken. There is currently no way to provide the callchain and other information, because the hardware sampler does not collect this information. Therefore prohibit sampling when the user requests a callchain graph from the hardware sampler. Return -EOPNOTSUPP to the user in this case. If call chains are really wanted, users need to specify software event cpu-clock to get the callchain information from a software event. Signed-off-by: Thomas Richter Reviewed-by: Sumanth Korikkar Signed-off-by: Heiko Carstens

s390/setup: init jump labels before command line parsing

2020-06-29T14:28:39+00:00

Command line parameters might set static keys. This is true for s390 at least since commit 6471384af2a6 ("mm: security: introduce init_on_alloc=1 and init_on_free=1 boot options"). To avoid the following WARN: static_key_enable_cpuslocked(): static key 'init_on_alloc+0x0/0x40' used before call to jump_label_init() call jump_label_init() just before parse_early_param(). jump_label_init() is safe to call multiple times (x86 does that), doesn't do any memory allocations and hence should be safe to call that early. Fixes: 6471384af2a6 ("mm: security: introduce init_on_alloc=1 and init_on_free=1 boot options") Cc: # 5.3: d6df52e9996d: s390/maccess: add no DAT mode to kernel_write Cc: # 5.3 Reviewed-by: Heiko Carstens Signed-off-by: Vasily Gorbik Signed-off-by: Heiko Carstens

s390/debug: avoid kernel warning on too large number of pages

2020-06-23T12:05:55+00:00

When specifying insanely large debug buffers a kernel warning is printed. The debug code does handle the error gracefully, though. Instead of duplicating the check let us silence the warning to avoid crashes when panic_on_warn is used. Signed-off-by: Christian Borntraeger Reviewed-by: Heiko Carstens Signed-off-by: Heiko Carstens

s390/kasan: fix early pgm check handler execution

2020-06-23T12:05:50+00:00

Currently if early_pgm_check_handler is called it ends up in pgm check loop. The problem is that early_pgm_check_handler is instrumented by KASAN but executed without DAT flag enabled which leads to addressing exception when KASAN checks try to access shadow memory. Fix that by executing early handlers with DAT flag on under KASAN as expected. Reported-and-tested-by: Alexander Egorenkov Reviewed-by: Heiko Carstens Signed-off-by: Vasily Gorbik Signed-off-by: Heiko Carstens

s390: fix system call single stepping

2020-06-23T12:05:45+00:00

When single stepping an svc instruction on s390, the kernel is entered with a PER program check interruption. The program check handler than jumps to the system call handler by reloading the PSW. The code didn't set GPR13 to the thread pointer in struct task_struct. This made the kernel access invalid memory while trying to fetch the syscall function address. Fix this by always assigned GPR13 after .Lsysc_per. Fixes: 0b0ed657fe00 ("s390: remove critical section cleanup from entry.S") Reported-and-tested-by: Christian Borntraeger Signed-off-by: Sven Schnelle Reviewed-by: Heiko Carstens Signed-off-by: Heiko Carstens

Merge tag 's390-5.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

2020-06-20T19:31:08+00:00

Pull s390 fixes from Vasily Gorbik: - a few ptrace fixes mostly for strace and seccomp_bpf kernel tests findings - cleanup unused pm callbacks in virtio ccw - replace kmalloc + memset with kzalloc in crypto - use $(LD) for vDSO linkage to make clang happy - fix vDSO clock_getres() to preserve the same behaviour as posix_get_hrtimer_res() - fix workqueue cpumask warning when NUMA=n and nr_node_ids=2 - reduce SLSB writes during input processing, improve warnings and cleanup qdio_data usage in qdio - a few fixes to use scnprintf() instead of snprintf() * tag 's390-5.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: s390: fix syscall_get_error for compat processes s390/qdio: warn about unexpected SLSB states s390/qdio: clean up usage of qdio_data s390/numa: let NODES_SHIFT depend on NEED_MULTIPLE_NODES s390/vdso: fix vDSO clock_getres() s390/vdso: Use $(LD) instead of $(CC) to link vDSO s390/protvirt: use scnprintf() instead of snprintf() s390: use scnprintf() in sys_##_prefix##_##_name##_show s390/crypto: use scnprintf() instead of snprintf() s390/zcrypt: use kzalloc s390/virtio: remove unused pm callbacks s390/qdio: reduce SLSB writes during Input Queue processing selftests/seccomp: s390 shares the syscall and return value register s390/ptrace: fix setting syscall number s390/ptrace: pass invalid syscall numbers to tracing s390/ptrace: return -ENOSYS when invalid syscall is supplied s390/seccomp: pass syscall arguments via seccomp_data s390/qdio: fine-tune SLSB update

maccess: rename probe_kernel_{read,write} to copy_{from,to}_kernel_nofault

2020-06-17T17:57:41+00:00

Better describe what these functions do. Suggested-by: Linus Torvalds Signed-off-by: Christoph Hellwig Signed-off-by: Linus Torvalds