From 860749038f508617c8fc31b8292b4019b1e621ba Mon Sep 17 00:00:00 2001

From: Franck Bui <fbui@suse.com>

Date: Thu, 16 Jul 2020 21:22:37 +0200

Subject: [PATCH] vconsole-setup: downgrade log message when setting font fails

 on dummy console

Since commit 883eb9be985fd86d9cabe967eeeab91cdd396a81, vconsole-setup might be

called again to operate on dummy console where font operations are not

supported but where it's still important to have the correct keymap set [0][1].

vconsole-setup is mainly called by udev but can also be run via a dependency of

an early service. Both cases might end up calling vconsole-setup on the dummy

console.

The first case can happen during early boot even on systems that use (instead

of the dummy console) a "simple" video console driver supporting font

operations (such as vgacon) until a more specific driver (such as i915) takes

the console over. While this is happening vgacon is deactivated and temporarly

replaced by the dummy console [2].

There are also other cases where systemd-vconsole-setup might be called on

dummy console especially during (very) early boot. Indeed

systemd-vconsole-setup.service might be pulled in by early interactive services

such as 'dracut-cmdline-ask.service` which is run before udev.

If that happens on platforms with no grapical HWs (such as embedded ARM) or

with dummy console initially installed until a driver takes over (like Xen and

xen-fbfront) then setting font will fail.

Therefore this patch downgrades the log message emitted when setting font fails

to LOG_DEBUG and when font operations is not implemented like it's the case for

the dummy console.

Fixes: #16406.

[0] https://github.com/systemd/systemd/issues/10826

[1] https://bugzilla.redhat.com/show_bug.cgi?id=1652473

[2] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/gpu/vga/vgaarb.c?h=v5.7#n204

(cherry picked from commit 0ef1adf51274960358e852d3bc36ae6c288a70d9)

Resolves: #1889996

---

 src/vconsole/vconsole-setup.c | 18 ++++++++++++++----

 1 file changed, 14 insertions(+), 4 deletions(-)

diff --git a/src/vconsole/vconsole-setup.c b/src/vconsole/vconsole-setup.c

index f162d29220..1b406c0bc5 100644

--- a/src/vconsole/vconsole-setup.c

+++ b/src/vconsole/vconsole-setup.c

@@ -222,6 +222,7 @@ static void setup_remaining_vcs(int src_fd, unsigned src_idx, bool utf8) {

         _cleanup_free_ struct unipair* unipairs = NULL;

         _cleanup_free_ void *fontbuf = NULL;

         unsigned i;

+        int log_level;

         int r;

         unipairs = new(struct unipair, USHRT_MAX);

@@ -230,11 +231,20 @@ static void setup_remaining_vcs(int src_fd, unsigned src_idx, bool utf8) {

                 return;

         }

+        log_level = LOG_WARNING;

+

         /* get metadata of the current font (width, height, count) */

         r = ioctl(src_fd, KDFONTOP, &cfo;;

-        if (r < 0)

-                log_warning_errno(errno, "KD_FONT_OP_GET failed while trying to get the font metadata: %m");

-        else {

+        if (r < 0) {

+                /* We might be called to operate on the dummy console (to setup keymap

+                 * mainly) when fbcon deferred takeover is used for example. In such case,

+                 * setting font is not supported and is expected to fail. */

+                if (errno == ENOSYS)

+                        log_level = LOG_DEBUG;

+

+                log_full_errno(log_level, errno,

+                               "KD_FONT_OP_GET failed while trying to get the font metadata: %m");

+        } else {

                 /* verify parameter sanity first */

                 if (cfo.width > 32 || cfo.height > 32 || cfo.charcount > 512)

                         log_warning("Invalid font metadata - width: %u (max 32), height: %u (max 32), count: %u (max 512)",

@@ -269,7 +279,7 @@ static void setup_remaining_vcs(int src_fd, unsigned src_idx, bool utf8) {

         }

         if (cfo.op != KD_FONT_OP_SET)

-                log_warning("Fonts will not be copied to remaining consoles");

+                log_full(log_level, "Fonts will not be copied to remaining consoles");

         for (i = 1; i <= 63; i++) {

                 char ttyname[sizeof("/dev/tty63")];