kernel/linux.git/tools/kvm, branch v6.12.80

tools/kvm_stat: use canonical ftrace path

2023-03-29T10:52:08+00:00

The canonical location for the tracefs filesystem is at /sys/kernel/tracing. But, from Documentation/trace/ftrace.rst: Before 4.1, all ftrace tracing control files were within the debugfs file system, which is typically located at /sys/kernel/debug/tracing. For backward compatibility, when mounting the debugfs file system, the tracefs file system will be automatically mounted at: /sys/kernel/debug/tracing A comment in kvm_stat still refers to this older debugfs path, so let's update it to avoid confusion. Link: https://lkml.kernel.org/r/20230313211746.1541525-3-zwisler@kernel.org Cc: "Tobin C. Harding" Cc: Andrew Morton Cc: Mark Rutland Cc: Masami Hiramatsu Cc: Shuah Khan Cc: Tycho Andersen Acked-by: Paolo Bonzini Reviewed-by: Steven Rostedt (Google) Reviewed-by: Mukesh Ojha Signed-off-by: Ross Zwisler Signed-off-by: Steven Rostedt (Google)

tools/kvm_stat: update exit reasons for vmx/svm/aarch64/userspace

2022-11-09T17:26:52+00:00

Update EXIT_REASONS from source, including VMX_EXIT_REASONS, SVM_EXIT_REASONS, AARCH64_EXIT_REASONS, USERSPACE_EXIT_REASONS. Signed-off-by: Rong Tao Message-Id: Signed-off-by: Paolo Bonzini

tools/kvm_stat: fix incorrect detection of debugfs

2022-11-09T17:26:52+00:00

The first field in /proc/mounts can be influenced by unprivileged users through the widespread `fusermount` setuid-root program. Example: ``` user$ mkdir ~/mydebugfs user$ export _FUSE_COMMFD=0 user$ fusermount ~/mydebugfs -ononempty,fsname=debugfs user$ grep debugfs /proc/mounts debugfs /home/user/mydebugfs fuse rw,nosuid,nodev,relatime,user_id=1000,group_id=100 0 0 ``` If there is no debugfs already mounted in the system then this can be used by unprivileged users to trick kvm_stat into using a user controlled file system location for obtaining KVM statistics. Even though the root user is not allowed to access non-root FUSE mounts for security reasons, the unprivileged user can unmount the FUSE mount before kvm_stat uses the mounted path. If it wins the race, kvm_stat will read from the location where the FUSE mount resided. Note that the files in debugfs are only opened for reading, so the attacker can cause very large data to be read in by kvm_stat, or fake data to be processed, but there should be no viable way to turn this into a privilege escalation. The fix is simply to use the file system type field instead. Whitespace in the mount path is escaped in /proc/mounts thus no further safety measures in the parsing should be necessary to make this correct. Message-Id: <20221103135927.13656-1-matthias.gerstner@suse.de> Signed-off-by: Matthias Gerstner Signed-off-by: Paolo Bonzini

tools/kvm_stat: fix display of error when multiple processes are found

2022-06-15T12:14:20+00:00

Instead of printing an error message, kvm_stat script fails when we restrict statistics to a guest by its name and there are multiple guests with such name: # kvm_stat -g my_vm Traceback (most recent call last): File "/usr/bin/kvm_stat", line 1819, in main() File "/usr/bin/kvm_stat", line 1779, in main options = get_options() File "/usr/bin/kvm_stat", line 1718, in get_options options = argparser.parse_args() File "/usr/lib64/python3.10/argparse.py", line 1825, in parse_args args, argv = self.parse_known_args(args, namespace) File "/usr/lib64/python3.10/argparse.py", line 1858, in parse_known_args namespace, args = self._parse_known_args(args, namespace) File "/usr/lib64/python3.10/argparse.py", line 2067, in _parse_known_args start_index = consume_optional(start_index) File "/usr/lib64/python3.10/argparse.py", line 2007, in consume_optional take_action(action, args, option_string) File "/usr/lib64/python3.10/argparse.py", line 1935, in take_action action(self, namespace, argument_values, option_string) File "/usr/bin/kvm_stat", line 1649, in __call__ ' to specify the desired pid'.format(" ".join(pids))) TypeError: sequence item 0: expected str instance, int found To avoid this, it's needed to convert pids int values to strings before pass them to join(). Signed-off-by: Dmitry Klochkov Message-Id: <20220614121141.160689-1-kdmitry556@gmail.com> Signed-off-by: Paolo Bonzini

KVM: kvm_stat: do not show halt_wait_ns

2021-10-18T18:07:18+00:00

Similar to commit 111d0bda8eeb ("tools/kvm_stat: Exempt time-based counters"), we should not show timer values in kvm_stat. Remove the new halt_wait_ns. Fixes: 87bcc5fa092f ("KVM: stats: Add halt_wait_ns stats for all architectures") Cc: Jing Zhang Cc: Stefan Raspl Signed-off-by: Christian Borntraeger Reviewed-by: Stefan Raspl Message-Id: <20211006121724.4154-1-borntraeger@de.ibm.com> Signed-off-by: Paolo Bonzini

tools/kvm_stat: Fix documentation typo

2021-05-07T10:06:22+00:00

Makes the dash in front of option '-z' disappear in the generated man-page. Signed-off-by: Stefan Raspl Message-Id: <20210506140352.4178789-1-raspl@linux.ibm.com> Signed-off-by: Paolo Bonzini

tools/kvm_stat: Add restart delay

2021-03-30T17:07:09+00:00

If this service is enabled and the system rebooted, Systemd's initial attempt to start this unit file may fail in case the kvm module is not loaded. Since we did not specify a delay for the retries, Systemd restarts with a minimum delay a number of times before giving up and disabling the service. Which means a subsequent kvm module load will have kvm running without monitoring. Adding a delay to fix this. Signed-off-by: Stefan Raspl Message-Id: <20210325122949.1433271-1-raspl@linux.ibm.com> Signed-off-by: Paolo Bonzini

tools/kvm_stat: Exempt time-based counters

2020-12-12T00:18:51+00:00

The new counters halt_poll_success_ns and halt_poll_fail_ns do not count events. Instead they provide a time, and mess up our statistics. Therefore, we should exclude them. Removal is currently implemented with an exempt list. If more counters like these appear, we can think about a more general rule like excluding all fields name "*_ns", in case that's a standing convention. Signed-off-by: Stefan Raspl Tested-and-reported-by: Christian Borntraeger Message-Id: <20201208210829.101324-1-raspl@linux.ibm.com> Signed-off-by: Paolo Bonzini

tools/kvm_stat: add sample systemd unit file

2020-04-21T13:13:12+00:00

Add a sample unit file as a basis for systemd integration of kvm_stat logs. Signed-off-by: Stefan Raspl Message-Id: <20200402085705.61155-4-raspl@linux.ibm.com> Signed-off-by: Paolo Bonzini

tools/kvm_stat: Add command line switch '-L' to log to file

2020-04-21T13:13:12+00:00

To integrate with logrotate, we have a signal handler that will re-open the logfile. Assuming we have a systemd unit file with ExecStart=kvm_stat -dtc -s 10 -L /var/log/kvm_stat.csv ExecReload=/bin/kill -HUP $MAINPID and a logrotate config featuring postrotate /bin/systemctl reload kvm_stat.service endscript Then the overall flow will look like this: (1) systemd starts kvm_stat, logging to A. (2) At some point, logrotate runs, moving A to B. kvm_stat continues to write to B at this point. (3) After rotating, logrotate restarts the kvm_stat unit via systemctl. (4) The kvm_stat unit sends a SIGHUP to kvm_stat, finally making it switch over to writing to A again. Note that in order to keep the structure of the cvs output in tact, we make sure to, in contrast to the standard log format, only write the header once at the beginning of a file. This implies that the header is suppressed when appending to an existing file. Unlike with the standard format, where we append to an existing file by starting out with a header. Signed-off-by: Stefan Raspl Message-Id: <20200402085705.61155-3-raspl@linux.ibm.com> Signed-off-by: Paolo Bonzini