Pranavkumar Sawargaonkar <pranavkumar@xxxxxxxxxx> writes: > Hi Rusty, > > On 13 May 2013 08:22, Rusty Russell <rusty@xxxxxxxxxxxxxxx> wrote: >> Pranavkumar Sawargaonkar <pranavkumar@xxxxxxxxxx> writes: >>> Signed-off-by: Pranavkumar Sawargaonkar <pranavkumar@xxxxxxxxxx> >>> Signed-off-by: Anup Patel <anup.patel@xxxxxxxxxx> >>> --- >>> Documentation/virtual/virtio-spec.txt | 8 +++++++- >>> 1 file changed, 7 insertions(+), 1 deletion(-) >> >> OK, I applied this to the lyx master, with three changes: >> 1) Changed "filed" to "field". >> 2) Added ", or even acknowledging the feature" after "without >> initializing virtio queues". >> 3) Added an initial point to the Device Initialization section: >> >> 1. If the VIRTIO_CONSOLE_F_EMERG_WRITE feature is offered, the >> emerg_wr field of the configuration can be written at any time. Thus >> it should work for very early boot debugging output as well as >> catastophic OS failures (eg. virtio ring corruption). > > Thanks for applying this patch. > Have you also applied first patch ([PATCH V2 1/3] virtio: console: Add > emergency writeonly register to config space) > with this? (https://lkml.org/lkml/2013/5/6/169) Would like Amit's Ack, since he's de-facto console maintainer. I've reproduced it below. Cheers, Rusty. Subject: [PATCH V2 1/3] virtio: console: Add emergency writeonly register to config space Date: Mon, 6 May 2013 17:49:49 +0530 Message-Id: <1367842791-30285-2-git-send-email-pranavkumar@xxxxxxxxxx> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1367842791-30285-1-git-send-email-pranavkumar@xxxxxxxxxx> References: <1367842791-30285-1-git-send-email-pranavkumar@xxxxxxxxxx> X-Gm-Message-State: ALoCoQmDOoCdPmDpT+VgLwYAlJHmkUTB8sEAHVSbrNxWBzYgPHFT9rQ2A9dR8fToM81cHDZDppGx This patch adds an emerg_wr register (writeonly) in config space of virtio console device which can be used for debugging. Signed-off-by: Pranavkumar Sawargaonkar <pranavkumar@xxxxxxxxxx> Signed-off-by: Anup Patel <anup.patel@xxxxxxxxxx> Signed-off-by: Rusty Russell <rusty@xxxxxxxxxxxxxxx> --- include/uapi/linux/virtio_console.h | 3 +++ 1 file changed, 3 insertions(+) diff --git a/include/uapi/linux/virtio_console.h b/include/uapi/linux/virtio_console.h index ee13ab6..3fd0dce 100644 --- a/include/uapi/linux/virtio_console.h +++ b/include/uapi/linux/virtio_console.h @@ -38,6 +38,7 @@ /* Feature bits */ #define VIRTIO_CONSOLE_F_SIZE 0 /* Does host provide console size? */ #define VIRTIO_CONSOLE_F_MULTIPORT 1 /* Does host provide multiple ports? */ +#define VIRTIO_CONSOLE_F_EMERG_WRITE 2 /* Does host support emergency write? */ #define VIRTIO_CONSOLE_BAD_ID (~(u32)0) @@ -48,6 +49,8 @@ struct virtio_console_config { __u16 rows; /* max. number of ports this device can hold */ __u32 max_nr_ports; + /* emergency write register */ + __u32 emerg_wr; } __attribute__((packed)); /* _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/cucslists/listinfo/kvmarm
