On 22/11/2023 4:20 pm, Andrew Cooper wrote:
> On 22/11/2023 9:02 am, Jan Beulich wrote:
>> On 21.11.2023 21:15, Andrew Cooper wrote:
>>> @@ -913,33 +914,30 @@ static struct domain *__init create_dom0(const
>>> module_t *image,
>>> panic("Error creating d%uv0\n", domid);
>>>
>>> /* Grab the DOM0 command line. */
>>> - cmdline = image->string ? __va(image->string) : NULL;
>>> - if ( cmdline || kextra )
>>> + if ( image->string || kextra )
>>> {
>>> - static char __initdata dom0_cmdline[MAX_GUEST_CMDLINE];
>>> -
>>> - cmdline = cmdline_cook(cmdline, loader);
>>> - safe_strcpy(dom0_cmdline, cmdline);
>>> + if ( image->string )
>>> + safe_strcpy(cmdline, cmdline_cook(__va(image->string),
>>> loader));
>>>
>>> if ( kextra )
>>> /* kextra always includes exactly one leading space. */
>>> - safe_strcat(dom0_cmdline, kextra);
>>> + safe_strcat(cmdline, kextra);
>>>
>>> /* Append any extra parameters. */
>>> - if ( skip_ioapic_setup && !strstr(dom0_cmdline, "noapic") )
>>> - safe_strcat(dom0_cmdline, " noapic");
>>> + if ( skip_ioapic_setup && !strstr(cmdline, "noapic") )
>>> + safe_strcat(cmdline, " noapic");
>>> +
>>> if ( (strlen(acpi_param) == 0) && acpi_disabled )
>>> {
>>> printk("ACPI is disabled, notifying Domain 0 (acpi=off)\n");
>>> safe_strcpy(acpi_param, "off");
>>> }
>>> - if ( (strlen(acpi_param) != 0) && !strstr(dom0_cmdline, "acpi=") )
>>> +
>>> + if ( (strlen(acpi_param) != 0) && !strstr(cmdline, "acpi=") )
>> As you're touching this anyway, how about replacing the strlen() by just
>> *acpi_param? We don't really care exactly how long the string is. (As an
>> aside, strstr() uses like the one here are of course also pretty fragile.
>> But of course that's nothing to care about in this change.)
> There's the same pattern just above it, not touched, and this patch is
> already getting complicated.
>
> I think there's other cleanup to do here, so I'll defer it to later.
It turns out that the optimiser already makes this transformation.
I shan't admit to how long I've just spent thinking I had a problem with
my build...
~Andrew
