Re: [Qemu-devel] patch to swap SIGRTMIN + 1 and SIGRTMAX - 1

[Marlies Ruck <marlies.ruck@gmail.com>]

Hi,

Just wanted to follow up to see what your thoughts are.  Is it preferable
if I submit a PR to the Go runtime first?  That would mitigate concerns
about Go breaking on QEMU with this patch.

Thanks,
Marli

On Mon, Jul 1, 2019 at 3:04 PM Marlies Ruck <marlies.ruck@gmail.com> wrote:

> Hi All,
>
> You are correct, this would break Go binaries.  I was planning on
> submitting a PR to the Go runtime if my patch was accepted to QEMU.  The Go
> PR would ignore the failure to register a handler for SIGRTMAX - 1, just as
> it currently ignores the failure on SIGRTMAX (
> https://github.com/golang/go/blob/master/src/runtime/os_linux.go#L443).
> Does this seem reasonable to you?  My local set up has these patches to
> QEMU and Go and it allows me to run both Go guest programs, and guest
> programs that use SIGRTMIN + 1.
>
> Also, thank you Peter and Phil for your patience as this is my first time
> contributing to QEMU.  If you decide to use this patch, I'm happy to resend
> the patch via `git send email`.
>
> Thanks!
> Marli
>
>
>
> On Mon, Jul 1, 2019 at 2:08 AM Peter Maydell <peter.maydell@linaro.org>
> wrote:
>
>> On Sat, 29 Jun 2019 at 11:53, Philippe Mathieu-Daudé <philmd@redhat.com>
>> wrote:
>> >
>> > Hi Marlies,
>> >
>> > On 6/29/19 1:26 AM, Marlies Ruck wrote:
>> > > Hi,
>> > >
>> > > I just wanted to follow up since I sent this patch a week ago to make
>> sure
>> > > it was a received.  An ack would be appreciated.
>> >
>> > You did not Cc'ed the maintainer, so he likely missed it.
>> > See:
>> >
>> https://wiki.qemu.org/Contribute/SubmitAPatch#CC_the_relevant_maintainer
>> >
>> > $ ./scripts/get_maintainer.pl -f linux-user/signal.c
>> > Riku Voipio <riku.voipio@iki.fi> (maintainer:Linux user)
>> > Laurent Vivier <laurent@vivier.eu> (reviewer:Linux user)
>> >
>> > BTW you should also look at the next paragraph in this wiki page:
>> >
>> https://wiki.qemu.org/Contribute/SubmitAPatch#Do_not_send_as_an_attachment
>> >
>> > Since you credit Peter Maydell, it would be kind to Cc him too.
>>
>> I have a strong suspicion that if we applied this patch it would
>> break running a pile of Go binaries that currently work, which means
>> it's something we need to be cautious about. (The Go runtime special
>> cases the fact that when it tries to register some signals they don't
>> work, but will abort on startup I think if it can't register a handler
>> for SIGRTMAX-1, which will be the case after this patch.)
>>
>> thanks
>> -- PMM
>>
>