On 13.02.2024 04:43, Marek Marczykowski wrote: > On Mon, Feb 12, 2024 at 10:04:38AM +0100, Jan Beulich wrote: >> On 08.02.2024 23:00, Julien Grall wrote: >>> On 05/02/2024 13:27, Jan Beulich wrote: >>>> In preparation of dropping the register parameters from >>>> serial_[rt]x_interrupt() and in turn from IRQ handler functions, >>>> register state needs making available another way for the few key >>>> handlers which need it. Fake IRQ-like state. >>>> >>>> Signed-off-by: Jan Beulich <[email protected]> >>>> --- >>>> The use of guest_cpu_user_regs() in dbc_uart_poll() is inconsistent with >>>> other console poll functions we have, and it's unclear whether that's >>>> actually generally correct. >>> >>> Is it? Looking at ns16550_poll() we would pass guest_user_regs() if >>> run_in_exception() doesn't exist. But looking at the caller, no-on seems >>> to care about the 'regs'. So is this just a latent bug? >> >> What do you mean by "doesn't exist"? ns16550_poll() assumes it exists. >> And I can spot any use of guest_user_regs() on the respective generic >> or Arm-specific bug.c paths. >> >>> BTW, do you have an idea why the poll function is not run in an >>> exception handler? >> >> "The poll function" being which one? If you mean the one in xhci-dbc.c >> then that's why I had Cc-ed Marek. Moving him to To: - maybe that >> manages to finally catch his attention. > > TBH, I don't know. That's part of the original xue patch at > https://github.com/connojd/xue/blob/master/patches/xen-xue-dbgp.patch > and it works for me as it is.
"Works" meaning what? Doesn't crash on you? Or does also provide sensible output in _all_ cases (i.e. including when e.g. the poll happens to run on an idle vCPU)? Jan
