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

s390/perf: obtain sie_block from the right address

2022-06-09T08:30:45Z

commit c9bfb460c3e4da2462e16b0f0b200990b36b1dd2 upstream. Since commit 1179f170b6f0 ("s390: fix fpu restore in entry.S"), the sie_block pointer is located at empty1[1], but in sie_block() it was taken from empty1[0]. This leads to a random pointer being dereferenced, possibly causing system crash. This problem can be observed when running a simple guest with an endless loop and recording the cpu-clock event: sudo perf kvm --guestvmlinux= --guest top -e cpu-clock With this fix, the correct guest address is shown. Fixes: 1179f170b6f0 ("s390: fix fpu restore in entry.S") Cc: stable@vger.kernel.org Acked-by: Christian Borntraeger Acked-by: Claudio Imbrenda Reviewed-by: Heiko Carstens Signed-off-by: Nico Boehr Signed-off-by: Heiko Carstens Signed-off-by: Greg Kroah-Hartman

s390: get rid of oprofile leftovers

2021-04-18T19:32:02Z

perf_pmu_name() and perf_num_counters() are unused. Drop them. Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20210414134409.1266357-4-maz@kernel.org Signed-off-by: Heiko Carstens

s390: add error handling to perf_callchain_kernel

2019-10-31T16:20:54Z

perf_callchain_kernel stops neither when it encounters a garbage address, nor when it runs out of space. Fix both issues using x86 version as an inspiration. Signed-off-by: Ilya Leoshkevich Signed-off-by: Vasily Gorbik

s390/unwind: introduce stack unwind API

2019-05-02T11:54:11Z

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

s390: kernel: Remove redundant license text

2017-11-24T14:37:20Z

Now that the SPDX tag is in all arch/s390/kernel/ files, that identifies the license in a specific and legally-defined manner. So the extra GPL text wording can be removed as it is no longer needed at all. This is done on a quest to remove the 700+ different ways that files in the kernel describe the GPL license text. And there's unneeded stuff like the address (sometimes incorrect) for the FSF which is never needed. No copyright headers or other non-license-description text was removed. Cc: Martin Schwidefsky Cc: Heiko Carstens Cc: Peter Zijlstra Cc: Ingo Molnar Cc: Arnaldo Carvalho de Melo Cc: Alexander Shishkin Cc: Jiri Olsa Cc: Namhyung Kim Cc: "Paul E. McKenney" Signed-off-by: Greg Kroah-Hartman Signed-off-by: Martin Schwidefsky

s390: kernel: add SPDX identifiers to the remaining files

2017-11-24T14:37:12Z

It's good to have SPDX identifiers in all files to make it easier to audit the kernel tree for correct licenses. Update the arch/s390/kernel/ files with the correct SPDX license identifier based on the license text in the file itself. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This work is based on a script and data from Thomas Gleixner, Philippe Ombredanne, and Kate Stewart. Cc: Martin Schwidefsky Cc: Heiko Carstens Cc: Peter Zijlstra Cc: Ingo Molnar Cc: Arnaldo Carvalho de Melo Cc: Alexander Shishkin Cc: Jiri Olsa Cc: Namhyung Kim Cc: Thomas Gleixner Cc: Kate Stewart Cc: Philippe Ombredanne Signed-off-by: Greg Kroah-Hartman Signed-off-by: Martin Schwidefsky

s390/perf: fix null string in perf list pmu command

2017-06-12T14:26:00Z

Command 'perf list pmu' displays events which contain an invalid string "(null)=xxx", where xxx is the pmu event name, for example: cpum_cf/AES_BLOCKED_CYCLES,(null)=AES_BLOCKED_CYCLES/ This is not correct, the invalid string should not be displayed at all. It is caused by an obsolete term in the sysfs attribute file for each s390 CPUMF counter event. Reading from the sysfs file also displays the event name. Fix this by omitting the event name. This patch makes s390 CPUMF sysfs files consistent with other plattforms. This is an interface change between user and kernel but does not break anything. Reading from a counter event sysfs file should only list terms mentioned in the /sys/bus/event_source/devices//format directory. Name is not listed. Reported-by: Zvonko Kosic Signed-off-by: Thomas Richter Reviewed-by: Hendrik Brueckner Signed-off-by: Martin Schwidefsky

s390/dumpstack: restore reliable indicator for call traces

2016-10-17T12:44:30Z

Before merging all different stack tracers the call traces printed had an indicator if an entry can be considered reliable or not. Unreliable entries were put in braces, reliable not. Currently all lines contain these extra braces. This patch restores the old behaviour by adding an extra "reliable" parameter to the callback functions. Only show_trace makes currently use of it. Before: [ 0.804751] Call Trace: [ 0.804753] ([<000000000017d0e0>] try_to_wake_up+0x318/0x5e0) [ 0.804756] ([<0000000000161d64>] create_worker+0x174/0x1c0) After: [ 0.804751] Call Trace: [ 0.804753] ([<000000000017d0e0>] try_to_wake_up+0x318/0x5e0) [ 0.804756] [<0000000000161d64>] create_worker+0x174/0x1c0 Fixes: 758d39ebd3d5 ("s390/dumpstack: merge all four stack tracers") Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky

s390/perf: remove perf_release/reserver_sampling functions

2016-06-28T07:32:25Z

Now that the oprofile sampling code is gone there is only one user of the sampling facility left. Therefore the reserve and release functions can be removed. Signed-off-by: Heiko Carstens Reviewed-by: Hendrik Brueckner Signed-off-by: Martin Schwidefsky

perf core: Pass max stack as a perf_callchain_entry context

2016-05-17T02:11:50Z

This makes perf_callchain_{user,kernel}() receive the max stack as context for the perf_callchain_entry, instead of accessing the global sysctl_perf_event_max_stack. Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Alexei Starovoitov Cc: Brendan Gregg Cc: David Ahern Cc: Frederic Weisbecker Cc: He Kuang Cc: Jiri Olsa Cc: Linus Torvalds Cc: Masami Hiramatsu Cc: Milian Wolff Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Stephane Eranian Cc: Thomas Gleixner Cc: Vince Weaver Cc: Wang Nan Cc: Zefan Li Link: http://lkml.kernel.org/n/tip-kolmn1yo40p7jhswxwrc7rrd@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo