Skip to content

Commit

Permalink
Revert "sleep: offer hibernation only if the kernel image still exists"
Browse files Browse the repository at this point in the history 
This reverts commit edda446.

The kernel explicitly supports resuming with a different kernel than the one
used before hibernation. If this is something that shouldn't be supported, the
place to change this is in the kernel. We shouldn't censor something that this
exclusively in the kernel's domain.

People might be using this to switch kernels without restaring programs, and
we'd break this functionality for them.

Also, even if resuming with a different kernel was a bad idea, we don't really
prevent that with this check, since most users have more than one kernel and
can freely pick a different one from the menu. So this only affected the corner
case where the kernel has been removed, but there is no reason to single it
out.
  • Loading branch information
@keszybz
keszybz committed Dec 21, 2018
1 parent 44f52cc commit 8340b76
Show file tree
Hide file tree
Showing 3 changed files with 6 additions and 83 deletions.
3 changes: 0 additions & 3 deletions NEWS
View file
Expand Up @@ -175,9 +175,6 @@ CHANGES WITH 240 in spe:
* Most configuration options that previously accepted percentage values
now also accept permille values with the '‰' suffix (instead of '%').

* systemd-logind will offer hibernation only if the currently used
kernel image is still available on disk.

* systemd-resolved may now optionally use OpenSSL instead of GnuTLS for
DNS-over-TLS.

Expand Down
10 changes: 5 additions & 5 deletions src/login/logind-dbus.c
View file
Expand Up @@ -1779,11 +1779,11 @@ static int method_do_shutdown_or_sleep(
if (sleep_verb) {
r = can_sleep(sleep_verb);
if (r == -ENOSPC)
return sd_bus_error_set(error, BUS_ERROR_SLEEP_VERB_NOT_SUPPORTED, "Not enough swap space for hibernation");
if (r == -ENOMEDIUM)
return sd_bus_error_set(error, BUS_ERROR_SLEEP_VERB_NOT_SUPPORTED, "Kernel image has been removed, can't hibernate");
return sd_bus_error_set(error, BUS_ERROR_SLEEP_VERB_NOT_SUPPORTED,
"Not enough swap space for hibernation");
if (r == 0)
return sd_bus_error_setf(error, BUS_ERROR_SLEEP_VERB_NOT_SUPPORTED, "Sleep verb \"%s\" not supported", sleep_verb);
return sd_bus_error_setf(error, BUS_ERROR_SLEEP_VERB_NOT_SUPPORTED,
"Sleep verb \"%s\" not supported", sleep_verb);
if (r < 0)
return r;
}
Expand Down Expand Up @@ -2210,7 +2210,7 @@ static int method_can_shutdown_or_sleep(

if (sleep_verb) {
r = can_sleep(sleep_verb);
if (IN_SET(r, 0, -ENOSPC, -ENOMEDIUM))
if (IN_SET(r, 0, -ENOSPC))
return sd_bus_reply_method_return(message, "s", "na");
if (r < 0)
return r;
Expand Down
76 changes: 1 addition & 75 deletions src/shared/sleep-config.c
View file
Expand Up @@ -10,12 +10,9 @@
#include <stdio.h>
#include <string.h>
#include <sys/ioctl.h>
#include <sys/utsname.h>
#include <syslog.h>
#include <unistd.h>

#include "sd-id128.h"

#include "alloc-util.h"
#include "conf-parser.h"
#include "def.h"
Expand Down Expand Up @@ -293,72 +290,6 @@ static bool enough_swap_for_hibernation(void) {
return r;
}

static int kernel_exists(void) {
struct utsname u;
sd_id128_t m;
int i, r;

/* Do some superficial checks whether the kernel we are currently running is still around. If it isn't we
* shouldn't offer hibernation as we couldn't possible resume from hibernation again. Of course, this check is
* very superficial, as the kernel's mere existance is hardly enough to know whether the hibernate/resume cycle
* will succeed. However, the common case of kernel updates can be caught this way, and it's definitely worth
* covering that. */

for (i = 0;; i++) {
_cleanup_free_ char *path = NULL;

switch (i) {

case 0:
/* First, let's look in /lib/modules/`uname -r`/vmlinuz. This is where current Fedora places
* its RPM-managed kernels. It's a good place, as it means compiled vendor code is monopolized
* in /usr, and then the kernel image is stored along with its modules in the same
* hierarchy. It's also what our 'kernel-install' script is written for. */
if (uname(&u) < 0)
return log_debug_errno(errno, "Failed to acquire kernel release: %m");

path = strjoin("/lib/modules/", u.release, "/vmlinuz");
break;

case 1:
/* Secondly, let's look in /boot/vmlinuz-`uname -r`. This is where older Fedora and other
* distributions tend to place the kernel. */
path = strjoin("/boot/vmlinuz-", u.release);
break;

case 2:
/* For the other cases, we look in the EFI/boot partition, at the place where our
* "kernel-install" script copies the kernel on install by default. */
r = sd_id128_get_machine(&m);
if (r < 0)
return log_debug_errno(r, "Failed to read machine ID: %m");

(void) asprintf(&path, "/efi/" SD_ID128_FORMAT_STR "/%s/linux", SD_ID128_FORMAT_VAL(m), u.release);
break;
case 3:
(void) asprintf(&path, "/boot/" SD_ID128_FORMAT_STR "/%s/linux", SD_ID128_FORMAT_VAL(m), u.release);
break;
case 4:
(void) asprintf(&path, "/boot/efi/" SD_ID128_FORMAT_STR "/%s/linux", SD_ID128_FORMAT_VAL(m), u.release);
break;

default:
return false;
}

if (!path)
return -ENOMEM;

log_debug("Testing whether %s exists.", path);

if (access(path, F_OK) >= 0)
return true;

if (errno != ENOENT)
log_debug_errno(errno, "Failed to determine whether '%s' exists, ignoring: %m", path);
}
}

int read_fiemap(int fd, struct fiemap **ret) {
_cleanup_free_ struct fiemap *fiemap = NULL, *result_fiemap = NULL;
struct stat statinfo;
Expand Down Expand Up @@ -458,7 +389,7 @@ static bool can_s2h(void) {

FOREACH_STRING(p, "suspend", "hibernate") {
r = can_sleep_internal(p, false);
if (IN_SET(r, 0, -ENOSPC, -ENOMEDIUM, -EADV)) {
if (IN_SET(r, 0, -ENOSPC, -EADV)) {
log_debug("Unable to %s system.", p);
return false;
}
Expand Down Expand Up @@ -494,11 +425,6 @@ static int can_sleep_internal(const char *verb, bool check_allowed) {
if (streq(verb, "suspend"))
return true;

if (kernel_exists() <= 0) {
log_debug_errno(errno, "Couldn't find kernel, not offering hibernation.");
return -ENOMEDIUM;
}

if (!enough_swap_for_hibernation())
return -ENOSPC;

Expand Down

0 comments on commit 8340b76

Please sign in to comment.