Mikko Rapeli cdd824093f oeqa ssh.py: fix hangs in run()
When qemu machine hangs, the ssh commands done by tests
are not timing out. do_testimage() task has last logs like this:

DEBUG: time: 1673531086.3155053, endtime: 1673531686.315502

The test process is stuck for hours, or for ever if the
executing command or test case did not set a timeout correctly.
The default 300 second timeout is not working when target hangs.
Note that timeout is really a "inactive timeout" since data returned
by the process will reset the timeout.

Make the process stdout non-blocking so read() will always return
right away using os.set_blocking() available in python 3.5 and later.

Then change from python codec reader to plain read() and make
the ssh subprocess stdout non-blocking. Even with select()
making sure the file had input to be read, the codec reader was
trying to find more stuff and blocking for ever when process hangs.

While at it, add a small timeout to read data in larger chunks if
possible. This avoids reading data one or few characters at a time
and makes the debug logs more readable.

close() the stdout file in all cases after read loop is complete.

Then make sure to wait or kill the ssh subprocess in all cases.
Just reading the output stream and receiving EOF there does not mean
that the process exited, and wait() needs a timeout if the process
is hanging. In the end kill the process and return the return value
and captured output utf-8 encoded, just like before these changes.

This fixes ssh run() related deadlocks when a qemu target hangs
completely.

(From OE-Core rev: 3e1a4d572922eadc85ff6ac169722ad7ab118cf4)

Signed-off-by: Mikko Rapeli <mikko.rapeli@linaro.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
(cherry picked from commit 9c63970fce3a3d6029745252a6ec2bf9b9da862d)
Signed-off-by: Steve Sakoman <steve@sakoman.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
2023-03-06 15:09:42 +00:00

317 lines
11 KiB
Python

#
# Copyright (C) 2016 Intel Corporation
#
# SPDX-License-Identifier: MIT
#
import os
import time
import select
import logging
import subprocess
import codecs
from . import OETarget
class OESSHTarget(OETarget):
def __init__(self, logger, ip, server_ip, timeout=300, user='root',
port=None, server_port=0, **kwargs):
if not logger:
logger = logging.getLogger('target')
logger.setLevel(logging.INFO)
filePath = os.path.join(os.getcwd(), 'remoteTarget.log')
fileHandler = logging.FileHandler(filePath, 'w', 'utf-8')
formatter = logging.Formatter(
'%(asctime)s.%(msecs)03d %(levelname)s: %(message)s',
'%H:%M:%S')
fileHandler.setFormatter(formatter)
logger.addHandler(fileHandler)
super(OESSHTarget, self).__init__(logger)
self.ip = ip
self.server_ip = server_ip
self.server_port = server_port
self.timeout = timeout
self.user = user
ssh_options = [
'-o', 'ServerAliveCountMax=2',
'-o', 'ServerAliveInterval=30',
'-o', 'UserKnownHostsFile=/dev/null',
'-o', 'StrictHostKeyChecking=no',
'-o', 'LogLevel=ERROR'
]
self.ssh = ['ssh', '-l', self.user ] + ssh_options
self.scp = ['scp'] + ssh_options
if port:
self.ssh = self.ssh + [ '-p', port ]
self.scp = self.scp + [ '-P', port ]
self._monitor_dumper = None
self.target_dumper = None
def start(self, **kwargs):
pass
def stop(self, **kwargs):
pass
@property
def monitor_dumper(self):
return self._monitor_dumper
@monitor_dumper.setter
def monitor_dumper(self, dumper):
self._monitor_dumper = dumper
self.monitor_dumper.dump_monitor()
def _run(self, command, timeout=None, ignore_status=True):
"""
Runs command in target using SSHProcess.
"""
self.logger.debug("[Running]$ %s" % " ".join(command))
starttime = time.time()
status, output = SSHCall(command, self.logger, timeout)
self.logger.debug("[Command returned '%d' after %.2f seconds]"
"" % (status, time.time() - starttime))
if status and not ignore_status:
raise AssertionError("Command '%s' returned non-zero exit "
"status %d:\n%s" % (command, status, output))
return (status, output)
def run(self, command, timeout=None):
"""
Runs command in target.
command: Command to run on target.
timeout: <value>: Kill command after <val> seconds.
None: Kill command default value seconds.
0: No timeout, runs until return.
"""
targetCmd = 'export PATH=/usr/sbin:/sbin:/usr/bin:/bin; %s' % command
sshCmd = self.ssh + [self.ip, targetCmd]
if timeout:
processTimeout = timeout
elif timeout==0:
processTimeout = None
else:
processTimeout = self.timeout
status, output = self._run(sshCmd, processTimeout, True)
self.logger.debug('Command: %s\nStatus: %d Output: %s\n' % (command, status, output))
if (status == 255) and (('No route to host') in output):
if self.monitor_dumper:
self.monitor_dumper.dump_monitor()
if status == 255:
if self.target_dumper:
self.target_dumper.dump_target()
if self.monitor_dumper:
self.monitor_dumper.dump_monitor()
return (status, output)
def copyTo(self, localSrc, remoteDst):
"""
Copy file to target.
If local file is symlink, recreate symlink in target.
"""
if os.path.islink(localSrc):
link = os.readlink(localSrc)
dstDir, dstBase = os.path.split(remoteDst)
sshCmd = 'cd %s; ln -s %s %s' % (dstDir, link, dstBase)
return self.run(sshCmd)
else:
remotePath = '%s@%s:%s' % (self.user, self.ip, remoteDst)
scpCmd = self.scp + [localSrc, remotePath]
return self._run(scpCmd, ignore_status=False)
def copyFrom(self, remoteSrc, localDst, warn_on_failure=False):
"""
Copy file from target.
"""
remotePath = '%s@%s:%s' % (self.user, self.ip, remoteSrc)
scpCmd = self.scp + [remotePath, localDst]
(status, output) = self._run(scpCmd, ignore_status=warn_on_failure)
if warn_on_failure and status:
self.logger.warning("Copy returned non-zero exit status %d:\n%s" % (status, output))
return (status, output)
def copyDirTo(self, localSrc, remoteDst):
"""
Copy recursively localSrc directory to remoteDst in target.
"""
for root, dirs, files in os.walk(localSrc):
# Create directories in the target as needed
for d in dirs:
tmpDir = os.path.join(root, d).replace(localSrc, "")
newDir = os.path.join(remoteDst, tmpDir.lstrip("/"))
cmd = "mkdir -p %s" % newDir
self.run(cmd)
# Copy files into the target
for f in files:
tmpFile = os.path.join(root, f).replace(localSrc, "")
dstFile = os.path.join(remoteDst, tmpFile.lstrip("/"))
srcFile = os.path.join(root, f)
self.copyTo(srcFile, dstFile)
def deleteFiles(self, remotePath, files):
"""
Deletes files in target's remotePath.
"""
cmd = "rm"
if not isinstance(files, list):
files = [files]
for f in files:
cmd = "%s %s" % (cmd, os.path.join(remotePath, f))
self.run(cmd)
def deleteDir(self, remotePath):
"""
Deletes target's remotePath directory.
"""
cmd = "rmdir %s" % remotePath
self.run(cmd)
def deleteDirStructure(self, localPath, remotePath):
"""
Delete recursively localPath structure directory in target's remotePath.
This function is very usefult to delete a package that is installed in
the DUT and the host running the test has such package extracted in tmp
directory.
Example:
pwd: /home/user/tmp
tree: .
└── work
├── dir1
│   └── file1
└── dir2
localpath = "/home/user/tmp" and remotepath = "/home/user"
With the above variables this function will try to delete the
directory in the DUT in this order:
/home/user/work/dir1/file1
/home/user/work/dir1 (if dir is empty)
/home/user/work/dir2 (if dir is empty)
/home/user/work (if dir is empty)
"""
for root, dirs, files in os.walk(localPath, topdown=False):
# Delete files first
tmpDir = os.path.join(root).replace(localPath, "")
remoteDir = os.path.join(remotePath, tmpDir.lstrip("/"))
self.deleteFiles(remoteDir, files)
# Remove dirs if empty
for d in dirs:
tmpDir = os.path.join(root, d).replace(localPath, "")
remoteDir = os.path.join(remotePath, tmpDir.lstrip("/"))
self.deleteDir(remoteDir)
def SSHCall(command, logger, timeout=None, **opts):
def run():
nonlocal output
nonlocal process
output_raw = b''
starttime = time.time()
process = subprocess.Popen(command, **options)
if timeout:
endtime = starttime + timeout
eof = False
os.set_blocking(process.stdout.fileno(), False)
while time.time() < endtime and not eof:
try:
logger.debug('Waiting for process output: time: %s, endtime: %s' % (time.time(), endtime))
if select.select([process.stdout], [], [], 5)[0] != []:
# wait a bit for more data, tries to avoid reading single characters
time.sleep(0.2)
data = process.stdout.read()
if not data:
eof = True
else:
output_raw += data
# ignore errors to capture as much as possible
logger.debug('Partial data from SSH call:\n%s' % data.decode('utf-8', errors='ignore'))
endtime = time.time() + timeout
except InterruptedError:
logger.debug('InterruptedError')
continue
process.stdout.close()
# process hasn't returned yet
if not eof:
process.terminate()
time.sleep(5)
try:
process.kill()
except OSError:
logger.debug('OSError when killing process')
pass
endtime = time.time() - starttime
lastline = ("\nProcess killed - no output for %d seconds. Total"
" running time: %d seconds." % (timeout, endtime))
logger.debug('Received data from SSH call:\n%s ' % lastline)
output += lastline
else:
output_raw = process.communicate()[0]
output = output_raw.decode('utf-8', errors='ignore')
logger.debug('Data from SSH call:\n%s' % output.rstrip())
# timout or not, make sure process exits and is not hanging
if process.returncode == None:
try:
process.wait(timeout=5)
except TimeoutExpired:
try:
process.kill()
except OSError:
logger.debug('OSError')
pass
options = {
"stdout": subprocess.PIPE,
"stderr": subprocess.STDOUT,
"stdin": None,
"shell": False,
"bufsize": -1,
"start_new_session": True,
}
options.update(opts)
output = ''
process = None
# Unset DISPLAY which means we won't trigger SSH_ASKPASS
env = os.environ.copy()
if "DISPLAY" in env:
del env['DISPLAY']
options['env'] = env
try:
run()
except:
# Need to guard against a SystemExit or other exception ocurring
# whilst running and ensure we don't leave a process behind.
if process.poll() is None:
process.kill()
logger.debug('Something went wrong, killing SSH process')
raise
return (process.returncode, output.rstrip())