Re: [PATCH v2 4/5] qemu_passt: Deduplicate passt killing code

On Thu, 16 Feb 2023 14:32:51 +0100 Michal Privoznik <mprivozn(a)redhat.com&gt; wrote: > There are two places where we kill passt: > > 1) qemuPasstStop() - called transitively from qemuProcessStop(), > 2) qemuPasstStart() - after failed start. > > Now, the code from 2) lack error preservation (so if there's > another error during cleanup we might overwrite the original > error). Therefore, move the internals of qemuPasstStop() into a > separate function and call it from both places. > > Signed-off-by: Michal Privoznik <mprivozn(a)redhat.com&gt; > --- > src/qemu/qemu_passt.c | 23 +++++++++++++---------- > 1 file changed, 13 insertions(+), 10 deletions(-) > > diff --git a/src/qemu/qemu_passt.c b/src/qemu/qemu_passt.c > index 881205449b..a4cc9e7166 100644 > --- a/src/qemu/qemu_passt.c > +++ b/src/qemu/qemu_passt.c > @@ -102,11 +102,9 @@ qemuPasstAddNetProps(virDomainObj *vm, > } > > > -void > -qemuPasstStop(virDomainObj *vm, > - virDomainNetDef *net) > +static void > +qemuPasstKill(const char *pidfile) A minor comment, should you respin: I think it should be made clear that this is not the expected/normal way in which passt will terminate -- here or in the next patch. Removing the PID file is nice, but that's (usually) about it.

> { > - g_autofree char *pidfile = qemuPasstCreatePidFilename(vm, net); > virErrorPtr orig_err; > > virErrorPreserveLast(&orig_err); > @@ -118,6 +116,16 @@ qemuPasstStop(virDomainObj *vm, > } > > > +void > +qemuPasstStop(virDomainObj *vm, > + virDomainNetDef *net) > +{ > + g_autofree char *pidfile = qemuPasstCreatePidFilename(vm, net); > + > + qemuPasstKill(pidfile); > +} > + > + > int > qemuPasstSetupCgroup(virDomainObj *vm, > virDomainNetDef *net, > @@ -147,7 +155,6 @@ qemuPasstStart(virDomainObj *vm, > g_autofree char *errbuf = NULL; > char macaddr[VIR_MAC_STRING_BUFLEN]; > size_t i; > - pid_t pid = (pid_t) -1; > int exitstatus = 0; > int cmdret = 0; > > @@ -289,10 +296,6 @@ qemuPasstStart(virDomainObj *vm, > return 0; > > error: > - ignore_value(virPidFileReadPathIfLocked(pidfile, &pid)); > - if (pid != -1) > - virProcessKillPainfully(pid, true); > - unlink(pidfile); > - > + qemuPasstKill(pidfile); ...what takes care of terminating passt in case qemu doesn't start, now? The fact that the process is in the cgroup, right?