On 21/12/19 17:21, Peter Wu wrote:
> When the 'vga=' parameter is succeeded by another parameter, QEMU 4.2.0
> would refuse to start with a rather cryptic message:
>
> $ qemu-system-x86_64 -kernel /boot/vmlinuz-linux -append 'vga=792 quiet'
> qemu: can't parse 'vga' parameter: Invalid argument
>
> It was not clear whether this applied to the '-vga std' parameter or the
> '-append' one. Fix the parsing regression and clarify the error.
>
> Fixes: 133ef074bd ("hw/i386/pc: replace use of strtol with qemu_strtoui in x86_load_linux()")
> Cc: Sergio Lopez <slp@redhat.com>
> Signed-off-by: Peter Wu <peter@lekensteyn.nl>
> ---
> Hi,
>
> This fixes a regression in QEMU 4.2.0 where my existing scripts would
> fail to boot while it worked fine with QEMU 4.1.1.
>
> I do wonder whether QEMU has any business in strictly enforcing the
> contents of the kernel command line. Perhaps it should only warn about
> the issue, and not exit? Previously it would silently ignore bad values.
>
> Kind regards,
> Peter
> ---
> hw/i386/x86.c | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/hw/i386/x86.c b/hw/i386/x86.c
> index 394edc2f72..121650ae51 100644
> --- a/hw/i386/x86.c
> +++ b/hw/i386/x86.c
> @@ -508,6 +508,7 @@ void x86_load_linux(X86MachineState *x86ms,
> vmode = strstr(kernel_cmdline, "vga=");
> if (vmode) {
> unsigned int video_mode;
> + const char *end;
> int ret;
> /* skip "vga=" */
> vmode += 4;
> @@ -518,10 +519,9 @@ void x86_load_linux(X86MachineState *x86ms,
> } else if (!strncmp(vmode, "ask", 3)) {
> video_mode = 0xfffd;
> } else {
> - ret = qemu_strtoui(vmode, NULL, 0, &video_mode);
> - if (ret != 0) {
> - fprintf(stderr, "qemu: can't parse 'vga' parameter: %s\n",
> - strerror(-ret));
> + ret = qemu_strtoui(vmode, &end, 0, &video_mode);
> + if (ret != 0 || (*end && *end != ' ')) {
> + fprintf(stderr, "qemu: invalid 'vga=' kernel parameter.\n");
> exit(1);
> }
> }
>
Cc: qemu-stable@nongnu.org
Queued, thanks.