From 43b4f60da9b468ffb3e782d91b9c01c845a339af Mon Sep 17 00:00:00 2001
From: Ray Strode <rstrode@redhat.com>
Date: Fri, 17 Jul 2020 16:06:44 -0400
Subject: [PATCH] src: die during shutdown with everything else
plymouthd currently avoids getting killed at shutdown. This causes
filesystems to fail to remount read-only in some cases.
This commit changes things up so that plymouthd dies with everyone else,
but spawns a process to hold open the drm device that can keep the splash
up until the very end.
---
src/Makefile.am | 7 +++
src/main.c | 11 ++--
src/plugins/renderers/drm/Makefile.am | 3 +-
src/plugins/renderers/drm/plugin.c | 62 ++++++++++++++++++++++
src/plymouthd-drm-escrow.c | 18 +++++++
systemd-units/plymouth-halt.service.in | 1 +
systemd-units/plymouth-poweroff.service.in | 1 +
systemd-units/plymouth-reboot.service.in | 1 +
8 files changed, 100 insertions(+), 4 deletions(-)
create mode 100644 src/plymouthd-drm-escrow.c
diff --git a/src/Makefile.am b/src/Makefile.am
index 95ed019..78f3f78 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -1,52 +1,59 @@
SUBDIRS = libply libply-splash-core libply-splash-graphics . plugins client
if ENABLE_UPSTART_MONITORING
SUBDIRS += upstart-bridge
endif
AM_CPPFLAGS = -I$(top_srcdir) \
-I$(srcdir)/libply \
-I$(srcdir)/libply-splash-core \
-I$(srcdir) \
+ -DPLYMOUTH_DRM_ESCROW_DIRECTORY=\"$(libexecdir)/plymouth\" \
-DPLYMOUTH_LOG_DIRECTORY=\"$(localstatedir)/log\" \
-DPLYMOUTH_SPOOL_DIRECTORY=\"$(localstatedir)/spool/plymouth\" \
-DPLYMOUTH_TIME_DIRECTORY=\"$(localstatedir)/lib/plymouth/\" \
-DPLYMOUTH_LOGO_FILE=\"$(logofile)\"
plymouthdbindir = $(plymouthdaemondir)
plymouthdbin_PROGRAMS = plymouthd
plymouthd_CFLAGS = $(PLYMOUTH_CFLAGS) \
-rdynamic \
-DPLYMOUTH_PLUGIN_PATH=\"$(PLYMOUTH_PLUGIN_PATH)\" \
-DPLYMOUTH_THEME_PATH=\"$(PLYMOUTH_THEME_PATH)/\" \
-DPLYMOUTH_POLICY_DIR=\"$(PLYMOUTH_POLICY_DIR)/\" \
-DPLYMOUTH_RUNTIME_DIR=\"$(PLYMOUTH_RUNTIME_DIR)\" \
-DPLYMOUTH_CONF_DIR=\"$(PLYMOUTH_CONF_DIR)/\" \
-DPLYMOUTH_RUNTIME_THEME_PATH=\"$(PLYMOUTH_RUNTIME_THEME_PATH)/\"
plymouthd_LDADD = $(PLYMOUTH_LIBS) libply/libply.la libply-splash-core/libply-splash-core.la
plymouthd_SOURCES = \
ply-boot-protocol.h \
ply-boot-server.h \
ply-boot-server.c \
plugins/splash/details/plugin.c \
main.c
+escrowdir = $(libexecdir)/plymouth
+escrow_PROGRAMS = plymouthd-drm-escrow
+
+plymouthd_drm_escrow_LDFLAGS = -all-static
+plymouthd_drm_escrow_SOURCES = plymouthd-drm-escrow.c
+
plymouthdrundir = $(localstatedir)/run/plymouth
plymouthdspooldir = $(localstatedir)/spool/plymouth
plymouthdtimedir = $(localstatedir)/lib/plymouth
pkgconfigdir = $(libdir)/pkgconfig
pkgconfig_DATA = ply-splash-core.pc ply-splash-graphics.pc
plymouthd_defaultsdir = $(PLYMOUTH_POLICY_DIR)
dist_plymouthd_defaults_DATA = plymouthd.defaults
plymouthd_confdir = $(PLYMOUTH_CONF_DIR)
dist_plymouthd_conf_DATA = plymouthd.conf
install-data-hook:
-mkdir -p $(DESTDIR)$(plymouthdrundir)
-mkdir -p $(DESTDIR)$(plymouthdspooldir)
-mkdir -p $(DESTDIR)$(plymouthdtimedir)
EXTRA_DIST = ply-splash-core.pc.in ply-splash-graphics.pc.in
MAINTAINERCLEANFILES = Makefile.in
diff --git a/src/main.c b/src/main.c
index 8848ad0..8372f2f 100644
--- a/src/main.c
+++ b/src/main.c
@@ -2181,65 +2181,70 @@ main (int argc,
if (daemon_handle == NULL) {
ply_error ("plymouthd: cannot daemonize: %m");
return EX_UNAVAILABLE;
}
}
if (debug)
debug_buffer = ply_buffer_new ();
signal (SIGABRT, on_crash);
signal (SIGSEGV, on_crash);
/* before do anything we need to make sure we have a working
* environment.
*/
if (!initialize_environment (&state)) {
if (errno == 0) {
if (daemon_handle != NULL)
ply_detach_daemon (daemon_handle, 0);
return 0;
}
ply_error ("plymouthd: could not setup basic operating environment: %m");
if (daemon_handle != NULL)
ply_detach_daemon (daemon_handle, EX_OSERR);
return EX_OSERR;
}
/* Make the first byte in argv be '@' so that we can survive systemd's killing
- * spree when going from initrd to /, and so we stay alive all the way until
- * the power is killed at shutdown.
+ * spree when going from initrd to /
* http://www.freedesktop.org/wiki/Software/systemd/RootStorageDaemons
+ *
+ * If the system is shutting down, we let systemd slay us because otherwise we
+ * may prevent the root fs from getting remounted read-only.
*/
- argv[0][0] = '@';
+ if (state.mode != PLY_BOOT_SPLASH_MODE_SHUTDOWN &&
+ state.mode != PLY_BOOT_SPLASH_MODE_REBOOT) {
+ argv[0][0] = '@';
+ }
state.boot_server = start_boot_server (&state);
if (state.boot_server == NULL) {
ply_trace ("plymouthd is already running");
if (daemon_handle != NULL)
ply_detach_daemon (daemon_handle, EX_OK);
return EX_OK;
}
state.boot_buffer = ply_buffer_new ();
if (attach_to_session) {
state.should_be_attached = attach_to_session;
if (!attach_to_running_session (&state)) {
ply_trace ("could not redirect console session: %m");
if (!no_daemon)
ply_detach_daemon (daemon_handle, EX_UNAVAILABLE);
return EX_UNAVAILABLE;
}
}
state.progress = ply_progress_new ();
state.splash_delay = NAN;
state.device_timeout = NAN;
ply_progress_load_cache (state.progress,
get_cache_file_for_mode (state.mode));
diff --git a/src/plugins/renderers/drm/Makefile.am b/src/plugins/renderers/drm/Makefile.am
index 271b17f..22a819b 100644
--- a/src/plugins/renderers/drm/Makefile.am
+++ b/src/plugins/renderers/drm/Makefile.am
@@ -1,23 +1,24 @@
if ENABLE_DRM_RENDERER
AM_CPPFLAGS = -I$(top_srcdir) \
-I$(srcdir)/../../../libply \
-I$(srcdir)/../../../libply-splash-core \
-I$(srcdir)/../../.. \
-I$(srcdir)/../.. \
-I$(srcdir)/.. \
- -I$(srcdir)
+ -I$(srcdir) \
+ -DPLYMOUTH_DRM_ESCROW_DIRECTORY=\"$(libexecdir)/plymouth\"
plugindir = $(libdir)/plymouth/renderers
plugin_LTLIBRARIES = drm.la
drm_la_CFLAGS = $(PLYMOUTH_CFLAGS) $(DRM_CFLAGS)
drm_la_LDFLAGS = -module -avoid-version -export-dynamic
drm_la_LIBADD = $(PLYMOUTH_LIBS) $(DRM_LIBS) \
../../../libply/libply.la \
../../../libply-splash-core/libply-splash-core.la
drm_la_SOURCES = $(srcdir)/plugin.c
endif
MAINTAINERCLEANFILES = Makefile.in
diff --git a/src/plugins/renderers/drm/plugin.c b/src/plugins/renderers/drm/plugin.c
index 4dbf8da..38bae36 100644
--- a/src/plugins/renderers/drm/plugin.c
+++ b/src/plugins/renderers/drm/plugin.c
@@ -131,73 +131,79 @@ typedef struct
bool connected;
bool uses_hw_rotation;
} ply_output_t;
struct _ply_renderer_backend
{
ply_event_loop_t *loop;
ply_terminal_t *terminal;
int device_fd;
char *device_name;
drmModeRes *resources;
ply_renderer_input_source_t input_source;
ply_list_t *heads;
ply_hashtable_t *heads_by_controller_id;
ply_hashtable_t *output_buffers;
ply_output_t *outputs;
int outputs_len;
int connected_count;
int32_t dither_red;
int32_t dither_green;
int32_t dither_blue;
uint32_t is_active : 1;
uint32_t requires_explicit_flushing : 1;
uint32_t use_preferred_mode : 1;
+ uint32_t watching_for_termination : 1;
int panel_width;
int panel_height;
ply_pixel_buffer_rotation_t panel_rotation;
int panel_scale;
};
ply_renderer_plugin_interface_t *ply_renderer_backend_get_interface (void);
static bool open_input_source (ply_renderer_backend_t *backend,
ply_renderer_input_source_t *input_source);
static void flush_head (ply_renderer_backend_t *backend,
ply_renderer_head_t *head);
+static void close_device (ply_renderer_backend_t *backend);
+
+static void watch_for_termination (ply_renderer_backend_t *backend);
+static void stop_watching_for_termination (ply_renderer_backend_t *backend);
+
/* A small helper to determine if we should try to keep the current mode
* or pick the best mode ourselves, we keep the current mode only if the
* user specified a specific mode using video= on the commandline.
*/
static bool
should_use_preferred_mode (void)
{
bool use_preferred_mode = true;
if (ply_kernel_command_line_get_string_after_prefix ("video="))
use_preferred_mode = false;
ply_trace ("should_use_preferred_mode: %d", use_preferred_mode);
return use_preferred_mode;
}
static bool
ply_renderer_buffer_map (ply_renderer_backend_t *backend,
ply_renderer_buffer_t *buffer)
{
struct drm_mode_map_dumb map_dumb_buffer_request;
void *map_address;
if (buffer->map_address != MAP_FAILED) {
buffer->map_count++;
return true;
}
memset (&map_dumb_buffer_request, 0, sizeof(struct drm_mode_map_dumb));
@@ -918,158 +924,214 @@ static void
destroy_backend (ply_renderer_backend_t *backend)
{
ply_trace ("destroying renderer backend for device %s", backend->device_name);
free_heads (backend);
free (backend->device_name);
ply_hashtable_free (backend->output_buffers);
ply_hashtable_free (backend->heads_by_controller_id);
free (backend->outputs);
free (backend);
}
static void
activate (ply_renderer_backend_t *backend)
{
ply_renderer_head_t *head;
ply_list_node_t *node;
ply_trace ("taking master and scanning out");
backend->is_active = true;
drmSetMaster (backend->device_fd);
node = ply_list_get_first_node (backend->heads);
while (node != NULL) {
head = (ply_renderer_head_t *) ply_list_node_get_data (node);
/* Flush out any pending drawing to the buffer */
flush_head (backend, head);
node = ply_list_get_next_node (backend->heads, node);
}
+
+ watch_for_termination (backend);
}
static void
deactivate (ply_renderer_backend_t *backend)
{
ply_trace ("dropping master");
drmDropMaster (backend->device_fd);
backend->is_active = false;
+
+ stop_watching_for_termination (backend);
}
static void
on_active_vt_changed (ply_renderer_backend_t *backend)
{
if (ply_terminal_is_active (backend->terminal)) {
ply_trace ("activating on vt change");
activate (backend);
} else {
ply_trace ("deactivating on vt change");
deactivate (backend);
}
}
static bool
load_driver (ply_renderer_backend_t *backend)
{
int device_fd;
ply_trace ("Opening '%s'", backend->device_name);
device_fd = open (backend->device_name, O_RDWR);
if (device_fd < 0) {
ply_trace ("open failed: %m");
return false;
}
backend->device_fd = device_fd;
drmDropMaster (device_fd);
return true;
}
static void
unload_backend (ply_renderer_backend_t *backend)
{
if (backend == NULL)
return;
ply_trace ("unloading backend");
if (backend->device_fd >= 0) {
drmClose (backend->device_fd);
backend->device_fd = -1;
}
destroy_backend (backend);
backend = NULL;
}
+static void
+on_term_signal (ply_renderer_backend_t *backend)
+{
+ pid_t pid;
+
+ ply_trace ("got SIGTERM, launching drm escrow to protect splash, and dying");
+
+ pid = fork();
+
+ if (pid == 0) {
+ const char *argv[] = { PLYMOUTH_DRM_ESCROW_DIRECTORY "/plymouthd-drm-escrow", NULL };
+
+ dup (backend->device_fd);
+ execve (argv[0], (char * const *) argv, NULL);
+
+ ply_trace ("could not launch drm escrow process: %m");
+
+ _exit (1);
+ }
+
+
+ close_device (backend);
+
+ exit (0);
+}
+
+static void
+watch_for_termination (ply_renderer_backend_t *backend)
+{
+ if (backend->watching_for_termination)
+ return;
+
+ ply_trace ("watching for termination signal");
+ ply_event_loop_watch_signal (backend->loop, SIGTERM, (ply_event_handler_t) on_term_signal, backend);
+ backend->watching_for_termination = true;
+}
+
+static void
+stop_watching_for_termination (ply_renderer_backend_t *backend)
+{
+ if (!backend->watching_for_termination)
+ return;
+
+ ply_trace ("stopping watching for termination signal");
+ ply_event_loop_stop_watching_signal (backend->loop, SIGTERM);
+ backend->watching_for_termination = false;
+}
+
static bool
open_device (ply_renderer_backend_t *backend)
{
assert (backend != NULL);
assert (backend->device_name != NULL);
if (!load_driver (backend))
return false;
if (backend->terminal == NULL)
return true;
if (!ply_terminal_open (backend->terminal)) {
ply_trace ("could not open terminal: %m");
return false;
}
if (!ply_terminal_is_vt (backend->terminal)) {
ply_trace ("terminal is not a VT");
ply_terminal_close (backend->terminal);
return false;
}
ply_terminal_watch_for_active_vt_change (backend->terminal,
(ply_terminal_active_vt_changed_handler_t)
on_active_vt_changed,
backend);
+ watch_for_termination (backend);
+
return true;
}
static void
close_device (ply_renderer_backend_t *backend)
{
ply_trace ("closing device");
free_heads (backend);
+ stop_watching_for_termination (backend);
+
if (backend->terminal != NULL) {
ply_terminal_stop_watching_for_active_vt_change (backend->terminal,
(ply_terminal_active_vt_changed_handler_t)
on_active_vt_changed,
backend);
}
unload_backend (backend);
}
static void
output_get_controller_info (ply_renderer_backend_t *backend,
drmModeConnector *connector,
ply_output_t *output)
{
int i;
drmModeEncoder *encoder;
assert (backend != NULL);
output->possible_controllers = 0xffffffff;
for (i = 0; i < connector->count_encoders; i++) {
encoder = drmModeGetEncoder (backend->device_fd,
connector->encoders[i]);
if (encoder == NULL)
continue;
if (encoder->encoder_id == connector->encoder_id && encoder->crtc_id) {
diff --git a/src/plymouthd-drm-escrow.c b/src/plymouthd-drm-escrow.c
new file mode 100644
index 0000000..9097db9
--- /dev/null
+++ b/src/plymouthd-drm-escrow.c
@@ -0,0 +1,18 @@
+#include <signal.h>
+#include <unistd.h>
+
+int
+main(int argc, char **argv)
+{
+ signal (SIGTERM, SIG_IGN);
+
+ /* Make the first byte in argv be '@' so that we can survive systemd's killing
+ * spree until the power is killed at shutdown.
+ * http://www.freedesktop.org/wiki/Software/systemd/RootStorageDaemons
+ */
+ argv[0][0] = '@';
+
+ while (pause());
+
+ return 0;
+}
diff --git a/systemd-units/plymouth-halt.service.in b/systemd-units/plymouth-halt.service.in
index cb87c1f..00f7eed 100644
--- a/systemd-units/plymouth-halt.service.in
+++ b/systemd-units/plymouth-halt.service.in
@@ -1,13 +1,14 @@
[Unit]
Description=Show Plymouth Halt Screen
After=getty@tty1.service display-manager.service plymouth-start.service
Before=systemd-halt.service
DefaultDependencies=no
ConditionKernelCommandLine=!plymouth.enable=0
ConditionVirtualization=!container
[Service]
ExecStart=@PLYMOUTH_DAEMON_DIR@/plymouthd --mode=shutdown --attach-to-session
ExecStartPost=-@PLYMOUTH_CLIENT_DIR@/plymouth show-splash
+KillMode=none
Type=forking
RemainAfterExit=yes
diff --git a/systemd-units/plymouth-poweroff.service.in b/systemd-units/plymouth-poweroff.service.in
index cf05e47..a1f78eb 100644
--- a/systemd-units/plymouth-poweroff.service.in
+++ b/systemd-units/plymouth-poweroff.service.in
@@ -1,13 +1,14 @@
[Unit]
Description=Show Plymouth Power Off Screen
After=getty@tty1.service display-manager.service plymouth-start.service
Before=systemd-poweroff.service
DefaultDependencies=no
ConditionKernelCommandLine=!plymouth.enable=0
ConditionVirtualization=!container
[Service]
ExecStart=@PLYMOUTH_DAEMON_DIR@/plymouthd --mode=shutdown --attach-to-session
ExecStartPost=-@PLYMOUTH_CLIENT_DIR@/plymouth show-splash
+KillMode=none
Type=forking
RemainAfterExit=yes
diff --git a/systemd-units/plymouth-reboot.service.in b/systemd-units/plymouth-reboot.service.in
index 3624550..8fff576 100644
--- a/systemd-units/plymouth-reboot.service.in
+++ b/systemd-units/plymouth-reboot.service.in
@@ -1,13 +1,14 @@
[Unit]
Description=Show Plymouth Reboot Screen
After=getty@tty1.service display-manager.service plymouth-start.service
Before=systemd-reboot.service
DefaultDependencies=no
ConditionKernelCommandLine=!plymouth.enable=0
ConditionVirtualization=!container
[Service]
ExecStart=@PLYMOUTH_DAEMON_DIR@/plymouthd --mode=reboot --attach-to-session
ExecStartPost=-@PLYMOUTH_CLIENT_DIR@/plymouth show-splash
+KillMode=none
Type=forking
RemainAfterExit=yes
--
2.26.0