From: "Dr. David Alan Gilbert" <dave@treblig.org>
-M is used heavily in documentation and scripts, but isn't actually
documented anywhere.
Document it as equivalent to -machine.
Reported-by: Julian Andres Klode <jak@jak-linux.org>
Signed-off-by: Dr. David Alan Gilbert <dave@treblig.org>
---
qemu-options.hx | 12 +++++++-----
1 file changed, 7 insertions(+), 5 deletions(-)
diff --git a/qemu-options.hx b/qemu-options.hx
index fca2b7bc74..ec92723f10 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -44,6 +44,7 @@ DEF("machine", HAS_ARG, QEMU_OPTION_machine, \
#endif
" memory-backend='backend-id' specifies explicitly provided backend for main RAM (default=none)\n"
" cxl-fmw.0.targets.0=firsttarget,cxl-fmw.0.targets.1=secondtarget,cxl-fmw.0.size=size[,cxl-fmw.0.interleave-granularity=granularity]\n"
+ " sgx-epc.0.memdev=memid,sgx-epc.0.node=numaid\n"
" smp-cache.0.cache=cachename,smp-cache.0.topology=topologylevel\n",
QEMU_ARCH_ALL)
SRST
@@ -179,6 +180,9 @@ SRST
-machine cxl-fmw.0.targets.0=cxl.0,cxl-fmw.0.targets.1=cxl.1,cxl-fmw.0.size=128G,cxl-fmw.0.interleave-granularity=512
+ ``sgx-epc.0.memdev=@var{memid},sgx-epc.0.node=@var{numaid}``
+ Define an SGX EPC section.
+
``smp-cache.0.cache=cachename,smp-cache.0.topology=topologylevel``
Define cache properties for SMP system.
@@ -208,12 +212,10 @@ SRST
ERST
DEF("M", HAS_ARG, QEMU_OPTION_M,
- " sgx-epc.0.memdev=memid,sgx-epc.0.node=numaid\n",
- QEMU_ARCH_ALL)
-
+ "-M as -machine\n", QEMU_ARCH_ALL)
SRST
-``sgx-epc.0.memdev=@var{memid},sgx-epc.0.node=@var{numaid}``
- Define an SGX EPC section.
+``-M``
+ as -machine.
ERST
DEF("cpu", HAS_ARG, QEMU_OPTION_cpu,
--
2.52.0On 03/12/2025 14.15, dave@treblig.org wrote:
> From: "Dr. David Alan Gilbert" <dave@treblig.org>
>
> -M is used heavily in documentation and scripts, but isn't actually
> documented anywhere.
> Document it as equivalent to -machine.
>
> Reported-by: Julian Andres Klode <jak@jak-linux.org>
> Signed-off-by: Dr. David Alan Gilbert <dave@treblig.org>
> ---
> qemu-options.hx | 12 +++++++-----
> 1 file changed, 7 insertions(+), 5 deletions(-)
>
> diff --git a/qemu-options.hx b/qemu-options.hx
> index fca2b7bc74..ec92723f10 100644
> --- a/qemu-options.hx
> +++ b/qemu-options.hx
> @@ -44,6 +44,7 @@ DEF("machine", HAS_ARG, QEMU_OPTION_machine, \
> #endif
> " memory-backend='backend-id' specifies explicitly provided backend for main RAM (default=none)\n"
> " cxl-fmw.0.targets.0=firsttarget,cxl-fmw.0.targets.1=secondtarget,cxl-fmw.0.size=size[,cxl-fmw.0.interleave-granularity=granularity]\n"
> + " sgx-epc.0.memdev=memid,sgx-epc.0.node=numaid\n"
> " smp-cache.0.cache=cachename,smp-cache.0.topology=topologylevel\n",
> QEMU_ARCH_ALL)
> SRST
> @@ -179,6 +180,9 @@ SRST
>
> -machine cxl-fmw.0.targets.0=cxl.0,cxl-fmw.0.targets.1=cxl.1,cxl-fmw.0.size=128G,cxl-fmw.0.interleave-granularity=512
>
> + ``sgx-epc.0.memdev=@var{memid},sgx-epc.0.node=@var{numaid}``
> + Define an SGX EPC section.
> +
> ``smp-cache.0.cache=cachename,smp-cache.0.topology=topologylevel``
> Define cache properties for SMP system.
>
> @@ -208,12 +212,10 @@ SRST
> ERST
>
> DEF("M", HAS_ARG, QEMU_OPTION_M,
> - " sgx-epc.0.memdev=memid,sgx-epc.0.node=numaid\n",
> - QEMU_ARCH_ALL)
> -
> + "-M as -machine\n", QEMU_ARCH_ALL)
> SRST
> -``sgx-epc.0.memdev=@var{memid},sgx-epc.0.node=@var{numaid}``
> - Define an SGX EPC section.
> +``-M``
> + as -machine.
> ERST
>
> DEF("cpu", HAS_ARG, QEMU_OPTION_cpu,
Reviewed-by: Thomas Huth <thuth@redhat.com>
dave@treblig.org writes:
> From: "Dr. David Alan Gilbert" <dave@treblig.org>
>
> -M is used heavily in documentation and scripts, but isn't actually
> documented anywhere.
> Document it as equivalent to -machine.
>
> Reported-by: Julian Andres Klode <jak@jak-linux.org>
> Signed-off-by: Dr. David Alan Gilbert <dave@treblig.org>
> ---
> qemu-options.hx | 12 +++++++-----
> 1 file changed, 7 insertions(+), 5 deletions(-)
>
> diff --git a/qemu-options.hx b/qemu-options.hx
> index fca2b7bc74..ec92723f10 100644
> --- a/qemu-options.hx
> +++ b/qemu-options.hx
> @@ -44,6 +44,7 @@ DEF("machine", HAS_ARG, QEMU_OPTION_machine, \
> #endif
> " memory-backend='backend-id' specifies explicitly provided backend for main RAM (default=none)\n"
> " cxl-fmw.0.targets.0=firsttarget,cxl-fmw.0.targets.1=secondtarget,cxl-fmw.0.size=size[,cxl-fmw.0.interleave-granularity=granularity]\n"
> + " sgx-epc.0.memdev=memid,sgx-epc.0.node=numaid\n"
> " smp-cache.0.cache=cachename,smp-cache.0.topology=topologylevel\n",
> QEMU_ARCH_ALL)
> SRST
> @@ -179,6 +180,9 @@ SRST
>
> -machine cxl-fmw.0.targets.0=cxl.0,cxl-fmw.0.targets.1=cxl.1,cxl-fmw.0.size=128G,cxl-fmw.0.interleave-granularity=512
>
> + ``sgx-epc.0.memdev=@var{memid},sgx-epc.0.node=@var{numaid}``
> + Define an SGX EPC section.
> +
This seems unrelated.
> ``smp-cache.0.cache=cachename,smp-cache.0.topology=topologylevel``
> Define cache properties for SMP system.
>
> @@ -208,12 +212,10 @@ SRST
> ERST
>
> DEF("M", HAS_ARG, QEMU_OPTION_M,
> - " sgx-epc.0.memdev=memid,sgx-epc.0.node=numaid\n",
> - QEMU_ARCH_ALL)
> -
> + "-M as -machine\n", QEMU_ARCH_ALL)
> SRST
> -``sgx-epc.0.memdev=@var{memid},sgx-epc.0.node=@var{numaid}``
> - Define an SGX EPC section.
> +``-M``
> + as -machine.
Did we have a merge conflict at some point that messed things up?
> ERST
>
> DEF("cpu", HAS_ARG, QEMU_OPTION_cpu,
--
Alex Bennée
Virtualisation Tech Lead @ Linaro
* Alex Bennée (alex.bennee@linaro.org) wrote:
> dave@treblig.org writes:
>
> > From: "Dr. David Alan Gilbert" <dave@treblig.org>
> >
> > -M is used heavily in documentation and scripts, but isn't actually
> > documented anywhere.
> > Document it as equivalent to -machine.
> >
> > Reported-by: Julian Andres Klode <jak@jak-linux.org>
> > Signed-off-by: Dr. David Alan Gilbert <dave@treblig.org>
> > ---
> > qemu-options.hx | 12 +++++++-----
> > 1 file changed, 7 insertions(+), 5 deletions(-)
> >
> > diff --git a/qemu-options.hx b/qemu-options.hx
> > index fca2b7bc74..ec92723f10 100644
> > --- a/qemu-options.hx
> > +++ b/qemu-options.hx
> > @@ -44,6 +44,7 @@ DEF("machine", HAS_ARG, QEMU_OPTION_machine, \
> > #endif
> > " memory-backend='backend-id' specifies explicitly provided backend for main RAM (default=none)\n"
> > " cxl-fmw.0.targets.0=firsttarget,cxl-fmw.0.targets.1=secondtarget,cxl-fmw.0.size=size[,cxl-fmw.0.interleave-granularity=granularity]\n"
> > + " sgx-epc.0.memdev=memid,sgx-epc.0.node=numaid\n"
> > " smp-cache.0.cache=cachename,smp-cache.0.topology=topologylevel\n",
> > QEMU_ARCH_ALL)
> > SRST
> > @@ -179,6 +180,9 @@ SRST
> >
> > -machine cxl-fmw.0.targets.0=cxl.0,cxl-fmw.0.targets.1=cxl.1,cxl-fmw.0.size=128G,cxl-fmw.0.interleave-granularity=512
> >
> > + ``sgx-epc.0.memdev=@var{memid},sgx-epc.0.node=@var{numaid}``
> > + Define an SGX EPC section.
> > +
>
> This seems unrelated.
>
> > ``smp-cache.0.cache=cachename,smp-cache.0.topology=topologylevel``
> > Define cache properties for SMP system.
> >
> > @@ -208,12 +212,10 @@ SRST
> > ERST
> >
> > DEF("M", HAS_ARG, QEMU_OPTION_M,
> > - " sgx-epc.0.memdev=memid,sgx-epc.0.node=numaid\n",
> > - QEMU_ARCH_ALL)
> > -
> > + "-M as -machine\n", QEMU_ARCH_ALL)
> > SRST
> > -``sgx-epc.0.memdev=@var{memid},sgx-epc.0.node=@var{numaid}``
> > - Define an SGX EPC section.
> > +``-M``
> > + as -machine.
>
> Did we have a merge conflict at some point that messed things up?
It's not clear - it was the only option hanging around in -M and it was
already appearing wrong in the man output.
I wondered if it was some requirement to have *something* in the -M
definition so thought it best to move it at the same time.
Dave
> > ERST
> >
> > DEF("cpu", HAS_ARG, QEMU_OPTION_cpu,
>
> --
> Alex Bennée
> Virtualisation Tech Lead @ Linaro
--
-----Open up your eyes, open up your mind, open up your code -------
/ Dr. David Alan Gilbert | Running GNU/Linux | Happy \
\ dave @ treblig.org | | In Hex /
\ _________________________|_____ http://www.treblig.org |_______/
On Wed, 3 Dec 2025 at 14:00, Dr. David Alan Gilbert <dave@treblig.org> wrote:
>
> * Alex Bennée (alex.bennee@linaro.org) wrote:
> > dave@treblig.org writes:
> >
> > > From: "Dr. David Alan Gilbert" <dave@treblig.org>
> > >
> > > -M is used heavily in documentation and scripts, but isn't actually
> > > documented anywhere.
> > > Document it as equivalent to -machine.
> > >
> > > Reported-by: Julian Andres Klode <jak@jak-linux.org>
> > > Signed-off-by: Dr. David Alan Gilbert <dave@treblig.org>
> > > ---
> > > qemu-options.hx | 12 +++++++-----
> > > 1 file changed, 7 insertions(+), 5 deletions(-)
> > >
> > > diff --git a/qemu-options.hx b/qemu-options.hx
> > > index fca2b7bc74..ec92723f10 100644
> > > --- a/qemu-options.hx
> > > +++ b/qemu-options.hx
> > > @@ -44,6 +44,7 @@ DEF("machine", HAS_ARG, QEMU_OPTION_machine, \
> > > #endif
> > > " memory-backend='backend-id' specifies explicitly provided backend for main RAM (default=none)\n"
> > > " cxl-fmw.0.targets.0=firsttarget,cxl-fmw.0.targets.1=secondtarget,cxl-fmw.0.size=size[,cxl-fmw.0.interleave-granularity=granularity]\n"
> > > + " sgx-epc.0.memdev=memid,sgx-epc.0.node=numaid\n"
> > > " smp-cache.0.cache=cachename,smp-cache.0.topology=topologylevel\n",
> > > QEMU_ARCH_ALL)
> > > SRST
> > > @@ -179,6 +180,9 @@ SRST
> > >
> > > -machine cxl-fmw.0.targets.0=cxl.0,cxl-fmw.0.targets.1=cxl.1,cxl-fmw.0.size=128G,cxl-fmw.0.interleave-granularity=512
> > >
> > > + ``sgx-epc.0.memdev=@var{memid},sgx-epc.0.node=@var{numaid}``
> > > + Define an SGX EPC section.
> > > +
> >
> > This seems unrelated.
> >
> > > ``smp-cache.0.cache=cachename,smp-cache.0.topology=topologylevel``
> > > Define cache properties for SMP system.
> > >
> > > @@ -208,12 +212,10 @@ SRST
> > > ERST
> > >
> > > DEF("M", HAS_ARG, QEMU_OPTION_M,
> > > - " sgx-epc.0.memdev=memid,sgx-epc.0.node=numaid\n",
> > > - QEMU_ARCH_ALL)
> > > -
> > > + "-M as -machine\n", QEMU_ARCH_ALL)
> > > SRST
> > > -``sgx-epc.0.memdev=@var{memid},sgx-epc.0.node=@var{numaid}``
> > > - Define an SGX EPC section.
> > > +``-M``
> > > + as -machine.
Surprisingly, this and -h/--help are our only two options where
we provide a short synonym. I note that this handling of -M
is not consistent with how we document -h/--help, where we
print both on a single line:
-h or -help display this help and exit
But it would be trickier to fit that in for -machine and
perhaps confusing given the suboptions.
> > Did we have a merge conflict at some point that messed things up?
>
> It's not clear - it was the only option hanging around in -M and it was
> already appearing wrong in the man output.
> I wondered if it was some requirement to have *something* in the -M
> definition so thought it best to move it at the same time.
It looks like this was incorrectly added under -M by
commit dfce81f1b9 ("vl: Add sgx compound properties to expose
SGX EPC sections to guest"), which should have put it under
-machine like all our other machine suboption documentation.
The result is that the sgx-epc documentation appears OK
in --help because the --help output just concatenates
everything so it gets tacked on after the -machine help,
but it is misrendered in the HTML docs:
https://qemu-project.gitlab.io/qemu/system/invocation.html
as it appears as if a top level option rather than one
indented to indicate that it's a machine sub-option.
So this change fixes that bug (and should ideally say so
in its commit message).
Before that it simply read
-HXCOMM Deprecated by -machine
-DEF("M", HAS_ARG, QEMU_OPTION_M, "", QEMU_ARCH_ALL)
(Commit dfce81f1b9 also silently dropped that "deprecated"
comment, which it shouldn't really have done.)
thanks
-- PMM
On 12/4/2025 12:06 AM, Peter Maydell wrote:
> On Wed, 3 Dec 2025 at 14:00, Dr. David Alan Gilbert <dave@treblig.org> wrote:
>>
>> * Alex Bennée (alex.bennee@linaro.org) wrote:
>>> dave@treblig.org writes:
>>>
>>>> From: "Dr. David Alan Gilbert" <dave@treblig.org>
>>>>
>>>> -M is used heavily in documentation and scripts, but isn't actually
>>>> documented anywhere.
>>>> Document it as equivalent to -machine.
>>>>
>>>> Reported-by: Julian Andres Klode <jak@jak-linux.org>
>>>> Signed-off-by: Dr. David Alan Gilbert <dave@treblig.org>
>>>> ---
>>>> qemu-options.hx | 12 +++++++-----
>>>> 1 file changed, 7 insertions(+), 5 deletions(-)
>>>>
>>>> diff --git a/qemu-options.hx b/qemu-options.hx
>>>> index fca2b7bc74..ec92723f10 100644
>>>> --- a/qemu-options.hx
>>>> +++ b/qemu-options.hx
>>>> @@ -44,6 +44,7 @@ DEF("machine", HAS_ARG, QEMU_OPTION_machine, \
>>>> #endif
>>>> " memory-backend='backend-id' specifies explicitly provided backend for main RAM (default=none)\n"
>>>> " cxl-fmw.0.targets.0=firsttarget,cxl-fmw.0.targets.1=secondtarget,cxl-fmw.0.size=size[,cxl-fmw.0.interleave-granularity=granularity]\n"
>>>> + " sgx-epc.0.memdev=memid,sgx-epc.0.node=numaid\n"
>>>> " smp-cache.0.cache=cachename,smp-cache.0.topology=topologylevel\n",
>>>> QEMU_ARCH_ALL)
>>>> SRST
>>>> @@ -179,6 +180,9 @@ SRST
>>>>
>>>> -machine cxl-fmw.0.targets.0=cxl.0,cxl-fmw.0.targets.1=cxl.1,cxl-fmw.0.size=128G,cxl-fmw.0.interleave-granularity=512
>>>>
>>>> + ``sgx-epc.0.memdev=@var{memid},sgx-epc.0.node=@var{numaid}``
>>>> + Define an SGX EPC section.
>>>> +
>>>
>>> This seems unrelated.
>>>
>>>> ``smp-cache.0.cache=cachename,smp-cache.0.topology=topologylevel``
>>>> Define cache properties for SMP system.
>>>>
>>>> @@ -208,12 +212,10 @@ SRST
>>>> ERST
>>>>
>>>> DEF("M", HAS_ARG, QEMU_OPTION_M,
>>>> - " sgx-epc.0.memdev=memid,sgx-epc.0.node=numaid\n",
>>>> - QEMU_ARCH_ALL)
>>>> -
>>>> + "-M as -machine\n", QEMU_ARCH_ALL)
>>>> SRST
>>>> -``sgx-epc.0.memdev=@var{memid},sgx-epc.0.node=@var{numaid}``
>>>> - Define an SGX EPC section.
>>>> +``-M``
>>>> + as -machine.
>
> Surprisingly, this and -h/--help are our only two options where
> we provide a short synonym. I note that this handling of -M
> is not consistent with how we document -h/--help, where we
> print both on a single line:
> -h or -help display this help and exit
>
> But it would be trickier to fit that in for -machine and
> perhaps confusing given the suboptions.
>
>>> Did we have a merge conflict at some point that messed things up?
>>
>> It's not clear - it was the only option hanging around in -M and it was
>> already appearing wrong in the man output.
>> I wondered if it was some requirement to have *something* in the -M
>> definition so thought it best to move it at the same time.
>
> It looks like this was incorrectly added under -M by
> commit dfce81f1b9 ("vl: Add sgx compound properties to expose
> SGX EPC sections to guest"), which should have put it under
> -machine like all our other machine suboption documentation.
>
> The result is that the sgx-epc documentation appears OK
> in --help because the --help output just concatenates
> everything so it gets tacked on after the -machine help,
> but it is misrendered in the HTML docs:
> https://qemu-project.gitlab.io/qemu/system/invocation.html
> as it appears as if a top level option rather than one
> indented to indicate that it's a machine sub-option.
> So this change fixes that bug (and should ideally say so
> in its commit message).
Yeah, I found this bug before and sent the fix:
https://lore.kernel.org/qemu-devel/20250714091953.448226-2-xiaoyao.li@intel.com/
But I was occupied with other stuff then so that had no time to sent out
the v2.
> Before that it simply read
> -HXCOMM Deprecated by -machine
> -DEF("M", HAS_ARG, QEMU_OPTION_M, "", QEMU_ARCH_ALL)
>
> (Commit dfce81f1b9 also silently dropped that "deprecated"
> comment, which it shouldn't really have done.)
>
> thanks
> -- PMM
>
* Peter Maydell (peter.maydell@linaro.org) wrote:
> On Wed, 3 Dec 2025 at 14:00, Dr. David Alan Gilbert <dave@treblig.org> wrote:
> >
> > * Alex Bennée (alex.bennee@linaro.org) wrote:
> > > dave@treblig.org writes:
> > >
> > > > From: "Dr. David Alan Gilbert" <dave@treblig.org>
> > > >
> > > > -M is used heavily in documentation and scripts, but isn't actually
> > > > documented anywhere.
> > > > Document it as equivalent to -machine.
> > > >
> > > > Reported-by: Julian Andres Klode <jak@jak-linux.org>
> > > > Signed-off-by: Dr. David Alan Gilbert <dave@treblig.org>
> > > > ---
> > > > qemu-options.hx | 12 +++++++-----
> > > > 1 file changed, 7 insertions(+), 5 deletions(-)
> > > >
> > > > diff --git a/qemu-options.hx b/qemu-options.hx
> > > > index fca2b7bc74..ec92723f10 100644
> > > > --- a/qemu-options.hx
> > > > +++ b/qemu-options.hx
> > > > @@ -44,6 +44,7 @@ DEF("machine", HAS_ARG, QEMU_OPTION_machine, \
> > > > #endif
> > > > " memory-backend='backend-id' specifies explicitly provided backend for main RAM (default=none)\n"
> > > > " cxl-fmw.0.targets.0=firsttarget,cxl-fmw.0.targets.1=secondtarget,cxl-fmw.0.size=size[,cxl-fmw.0.interleave-granularity=granularity]\n"
> > > > + " sgx-epc.0.memdev=memid,sgx-epc.0.node=numaid\n"
> > > > " smp-cache.0.cache=cachename,smp-cache.0.topology=topologylevel\n",
> > > > QEMU_ARCH_ALL)
> > > > SRST
> > > > @@ -179,6 +180,9 @@ SRST
> > > >
> > > > -machine cxl-fmw.0.targets.0=cxl.0,cxl-fmw.0.targets.1=cxl.1,cxl-fmw.0.size=128G,cxl-fmw.0.interleave-granularity=512
> > > >
> > > > + ``sgx-epc.0.memdev=@var{memid},sgx-epc.0.node=@var{numaid}``
> > > > + Define an SGX EPC section.
> > > > +
> > >
> > > This seems unrelated.
> > >
> > > > ``smp-cache.0.cache=cachename,smp-cache.0.topology=topologylevel``
> > > > Define cache properties for SMP system.
> > > >
> > > > @@ -208,12 +212,10 @@ SRST
> > > > ERST
> > > >
> > > > DEF("M", HAS_ARG, QEMU_OPTION_M,
> > > > - " sgx-epc.0.memdev=memid,sgx-epc.0.node=numaid\n",
> > > > - QEMU_ARCH_ALL)
> > > > -
> > > > + "-M as -machine\n", QEMU_ARCH_ALL)
> > > > SRST
> > > > -``sgx-epc.0.memdev=@var{memid},sgx-epc.0.node=@var{numaid}``
> > > > - Define an SGX EPC section.
> > > > +``-M``
> > > > + as -machine.
>
> Surprisingly, this and -h/--help are our only two options where
> we provide a short synonym. I note that this handling of -M
> is not consistent with how we document -h/--help, where we
> print both on a single line:
> -h or -help display this help and exit
>
> But it would be trickier to fit that in for -machine and
> perhaps confusing given the suboptions.
Right, that's one of the two reasons I kept it separate.
The other reason, is that I couldn't figure out how '-help' and '-h'
both got defined - why is the second DEF(...) not needed?
> > > Did we have a merge conflict at some point that messed things up?
> >
> > It's not clear - it was the only option hanging around in -M and it was
> > already appearing wrong in the man output.
> > I wondered if it was some requirement to have *something* in the -M
> > definition so thought it best to move it at the same time.
>
> It looks like this was incorrectly added under -M by
> commit dfce81f1b9 ("vl: Add sgx compound properties to expose
> SGX EPC sections to guest"), which should have put it under
> -machine like all our other machine suboption documentation.
>
> The result is that the sgx-epc documentation appears OK
> in --help because the --help output just concatenates
> everything so it gets tacked on after the -machine help,
> but it is misrendered in the HTML docs:
> https://qemu-project.gitlab.io/qemu/system/invocation.html
> as it appears as if a top level option rather than one
> indented to indicate that it's a machine sub-option.
> So this change fixes that bug (and should ideally say so
> in its commit message).
>
> Before that it simply read
> -HXCOMM Deprecated by -machine
> -DEF("M", HAS_ARG, QEMU_OPTION_M, "", QEMU_ARCH_ALL)
>
> (Commit dfce81f1b9 also silently dropped that "deprecated"
> comment, which it shouldn't really have done.)
Ah.
Dave
> thanks
> -- PMM
--
-----Open up your eyes, open up your mind, open up your code -------
/ Dr. David Alan Gilbert | Running GNU/Linux | Happy \
\ dave @ treblig.org | | In Hex /
\ _________________________|_____ http://www.treblig.org |_______/
On Wed, 3 Dec 2025 at 16:20, Dr. David Alan Gilbert <dave@treblig.org> wrote:
>
> * Peter Maydell (peter.maydell@linaro.org) wrote:
> > Surprisingly, this and -h/--help are our only two options where
> > we provide a short synonym. I note that this handling of -M
> > is not consistent with how we document -h/--help, where we
> > print both on a single line:
> > -h or -help display this help and exit
> >
> > But it would be trickier to fit that in for -machine and
> > perhaps confusing given the suboptions.
>
> Right, that's one of the two reasons I kept it separate.
> The other reason, is that I couldn't figure out how '-help' and '-h'
> both got defined - why is the second DEF(...) not needed?
A piece of delicious fudge lurking in system/vl.c: we have
this hardcoded entry in the qemu_options[] array before
the ones that are generated via the macro-magic from
qemu-options.hx:
{ "h", 0, QEMU_OPTION_h, QEMU_ARCH_ALL },
So we recognize -h on the command line and turn it into
QEMU_OPTION_h, the same as -help, but it doesn't result in
anything in the documentation (we leave that up to the
strings and RST in the DEF("help"...) section).
thanks
-- PMM
* Peter Maydell (peter.maydell@linaro.org) wrote:
> On Wed, 3 Dec 2025 at 16:20, Dr. David Alan Gilbert <dave@treblig.org> wrote:
> >
> > * Peter Maydell (peter.maydell@linaro.org) wrote:
> > > Surprisingly, this and -h/--help are our only two options where
> > > we provide a short synonym. I note that this handling of -M
> > > is not consistent with how we document -h/--help, where we
> > > print both on a single line:
> > > -h or -help display this help and exit
> > >
> > > But it would be trickier to fit that in for -machine and
> > > perhaps confusing given the suboptions.
> >
> > Right, that's one of the two reasons I kept it separate.
> > The other reason, is that I couldn't figure out how '-help' and '-h'
> > both got defined - why is the second DEF(...) not needed?
>
> A piece of delicious fudge lurking in system/vl.c: we have
> this hardcoded entry in the qemu_options[] array before
> the ones that are generated via the macro-magic from
> qemu-options.hx:
>
> { "h", 0, QEMU_OPTION_h, QEMU_ARCH_ALL },
>
> So we recognize -h on the command line and turn it into
> QEMU_OPTION_h, the same as -help, but it doesn't result in
> anything in the documentation (we leave that up to the
> strings and RST in the DEF("help"...) section).
Hah ok! I guess that fudge could be removed and make it the
same way -M works.
Dave
> thanks
> -- PMM
--
-----Open up your eyes, open up your mind, open up your code -------
/ Dr. David Alan Gilbert | Running GNU/Linux | Happy \
\ dave @ treblig.org | | In Hex /
\ _________________________|_____ http://www.treblig.org |_______/
On Wed, 3 Dec 2025 at 16:37, Dr. David Alan Gilbert <dave@treblig.org> wrote:
>
> * Peter Maydell (peter.maydell@linaro.org) wrote:
> > On Wed, 3 Dec 2025 at 16:20, Dr. David Alan Gilbert <dave@treblig.org> wrote:
> > >
> > > * Peter Maydell (peter.maydell@linaro.org) wrote:
> > > > Surprisingly, this and -h/--help are our only two options where
> > > > we provide a short synonym. I note that this handling of -M
> > > > is not consistent with how we document -h/--help, where we
> > > > print both on a single line:
> > > > -h or -help display this help and exit
> > > >
> > > > But it would be trickier to fit that in for -machine and
> > > > perhaps confusing given the suboptions.
> > >
> > > Right, that's one of the two reasons I kept it separate.
> > > The other reason, is that I couldn't figure out how '-help' and '-h'
> > > both got defined - why is the second DEF(...) not needed?
> >
> > A piece of delicious fudge lurking in system/vl.c: we have
> > this hardcoded entry in the qemu_options[] array before
> > the ones that are generated via the macro-magic from
> > qemu-options.hx:
> >
> > { "h", 0, QEMU_OPTION_h, QEMU_ARCH_ALL },
> >
> > So we recognize -h on the command line and turn it into
> > QEMU_OPTION_h, the same as -help, but it doesn't result in
> > anything in the documentation (we leave that up to the
> > strings and RST in the DEF("help"...) section).
>
> Hah ok! I guess that fudge could be removed and make it the
> same way -M works.
Yeah, I was pondering that. Also, we don't document --help in
the HTML docs, only -h.
-- PMM
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