Orphan cleanup is currently executed even if the file system has some
number of unknown ROCOMPAT features, which deletes inodes and frees
blocks, which could be very bad for some RO_COMPAT features,
especially the SNAPSHOT feature.
This patch skips the orphan cleanup if it contains readonly compatible
features not known by this ext4 implementation, which would prevent
the fs from being mounted (or remounted) readwrite.
The dcdbas driver can do an I/O write to cause a SMI to occur. The SMI handler
looks at certain registers and memory locations, so the SMI needs to happen
immediately. On some systems I/O writes are posted, though, causing the SMI to
happen well after the "outb" occurred, which causes random failures. Following
the "outb" with an "inb" forces the write to go through even if it is posted.
While trying to track down some NFS problems with BTRFS, I kept noticing I was
getting -EACCESS for no apparent reason. Eric Paris and printk() helped me
figure out that it was SELinux that was giving me grief, with the following
denial
Turns out this is because in d_obtain_alias if we can't find an alias we create
one and do all the normal instantiation stuff, but we don't do the
security_d_instantiate.
Usually we are protected from getting a hashed dentry that hasn't yet run
security_d_instantiate() by the parent's i_mutex, but obviously this isn't an
option there, so in order to deal with the case that a second thread comes in
and finds our new dentry before we get to run security_d_instantiate(), we go
ahead and call it if we find a dentry already. Eric assures me that this is ok
as the code checks to see if the dentry has been initialized already so calling
security_d_instantiate() against the same dentry multiple times is ok. With
this patch I'm no longer getting errant -EACCESS values.
If we call xs_close(), we're in one of two situations:
- Autoclose, which means we don't expect to resend a request
- bind+connect failed, which probably means the port is in use
When one of the two waits in nfs_commit_inode() is interrupted, it
returns a non-negative value, which causes nfs_wb_page() to think
that the operation was successful causing it to busy-loop rather
than exiting.
It also causes nfs_file_fsync() to incorrectly report the file as
being successfully committed to disk.
This patch fixes both problems by ensuring that we return an error
if the attempts to wait fail.
When destroying inherited events, we need to destroy groups too,
otherwise the event iteration in perf_event_exit_task_context() will
miss group siblings and we leak events with all the consequences.
On some servers there is a hardcoded EDID provided
in the vbios so that the driver will always see a
display connected even if something like a KVM
prevents traditional means like DDC or load
detection from working properly. Also most
server boards with DVI are not actually DVI, but
DVO connected to a virtual KVM service processor.
If we fail to detect a monitor via DDC or load
detection and a hardcoded EDID is available, use
it.
Additionally, when using the hardcoded EDID, use
a copy of it rather than the actual one stored
in the driver as the detect() and get_modes()
functions may free it if DDC is successful.
This fixes the virtual KVM on several internal
servers.
Signed-off-by: Alex Deucher <email address hidden>
Signed-off-by: Dave Airlie <email address hidden>
Signed-off-by: Greg Kroah-Hartman <email address hidden>
