>>> Lennart Poettering <lenn...@poettering.net> schrieb am 13.08.2020 um 11:13 in Nachricht <20200813091301.GF229811@gardel-login>: > eOn Do, 13.08.20 09:24, Ulrich Windl (ulrich.wi...@rz.uni‑regensburg.de) > wrote: > >> > systemd should really clearly log this (invalid PID and and in which >> > cgroup it was). Returning generic error message without any indication >> > what caused this error is not useful at all. >> >> Especially as there was no I/O error at all ;‑) Maybe EINVAL or ESRCH would >> have been a better error code. > > We generate EIO because the I/O data we read was bogus and can't > possible be correct. > > I really don't think the precise error code here matters much, as long > as we generate an error. > > ESRCH is not the right error, it suggests that there was a valiD PID > number but simply no matching process for it. But that's not the case > here, the PID "0" is not valid at all. > > Note that we'd probably generate EINVAL here, if this was a different > type of interface, i.e. some explicit syscall or so. But here we have > a read() call where we get the clearly borked data from, hence we > generate this as EIO and not EINVAL.
I disagree: EIO would suggest that no data could be read. In fact data was read, but data was invalid. This is not an I/O error. (Think about this: The compiler reads an invalid C program, and it says "I/O Error") ;-) > > Ultimately, which error code to generate is just bike‑shedding though... > > Lennart > > ‑‑ > Lennart Poettering, Berlin _______________________________________________ systemd-devel mailing list systemd-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/systemd-devel
