The variable "argument" will be set to an appropriate value a bit later.
Thus omit the explicit initialisation at the beginning.
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
The local variable "func_no" was assigned a value at two places.
But it was not read within this function. Thus delete it.
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
The kfree() function was called in one case by the
amdgpu_cgs_acpi_eval_object() function during error handling
even if the passed variable "obj" contained a null pointer.
* Adjust jump targets according to the Linux coding style convention.
* Delete unnecessary initialisations for the variables "obj"
and "params" then.
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
The drm_gem_object_unreference_unlocked() function tests whether
its argument is NULL and then returns immediately.
Thus the test around the call is not needed.
This issue was detected by using the Coccinelle software.
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
The drm_gem_object_unreference_unlocked() function tests whether
its argument is NULL and then returns immediately.
Thus the test around the call is not needed.
This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Found-by: Coccinelle
Signed-off-by: Edward O'Callaghan <funfunctor@folklore1984.net>
Reviewed-by: Tom St Denis <tom.stdenis@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
V.2: Fixup by hand to remove a few instances of redundant '()'
left over.
Found-by: Coccinelle
Signed-off-by: Edward O'Callaghan <funfunctor@folklore1984.net>
Reviewed-by: Tom St Denis <tom.stdenis@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Found-by: Coccinelle
Signed-off-by: Edward O'Callaghan <funfunctor@folklore1984.net>
Reviewed-by: Tom St Denis <tom.stdenis@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Found-by: Coccinelle
Signed-off-by: Edward O'Callaghan <funfunctor@folklore1984.net>
Reviewed-by: Tom St Denis <tom.stdenis@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Found-by: Coccinelle
Signed-off-by: Edward O'Callaghan <funfunctor@folklore1984.net>
Reviewed-by: Tom St Denis <tom.stdenis@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Found-by: Coccinelle
Signed-off-by: Edward O'Callaghan <funfunctor@folklore1984.net>
Reviewed-by: Tom St Denis <tom.stdenis@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Found-by: Coccinelle
Signed-off-by: Edward O'Callaghan <funfunctor@folklore1984.net>
Reviewed-by: Tom St Denis <tom.stdenis@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
DIDT is a power saving feature which helps limit power
consumption in order to hit a target power allocation.
v1: delete temp file added accidentally.
Signed-off-by: Rex Zhu <Rex.Zhu@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
This fixes a warning on big endian. Bitfields need to
be handled properly.
Cc: Arnd Bergmann <arnd@arndb.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
The message is harmless and confusing. On PX systems,
there is one ATIF method, but potentially multiple GPUs
leading to an error on the GPU with no backlight control.
Bug: https://bugzilla.kernel.org/show_bug.cgi?id=115011
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: Hans de Goede <jwrdegoede@fedoraproject.org>
commit d967be9b80 ("drm/radeon/ci: disable needless sclk changes")
introduces an unreachable if(C != C) conditional code section
flagged by coccinelle script bad_conditional.cocci:
Add a comment to make it clear that this is intentional.
Fixes: d967be9b80 ("drm/radeon/ci: disable needless sclk changes")
Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Just about all of amdgpu's connector probing functions try to acquire
runtime PM refs. If we try to do this in the context of
amdgpu_resume_kms by calling drm_helper_hpd_irq_event(), we end up
deadlocking the system.
Since we're guaranteed to be holding the spinlock for RPM in
amdgpu_resume_kms, and we already know the GPU is in working order, we
need to prevent the RPM helpers from trying to run during the initial
connector reprobe on resume.
There's a couple of solutions I've explored for fixing this, but this
one by far seems to be the simplest and most reliable (plus I'm pretty
sure that's what disable_depth is there for anyway).
Reproduction recipe:
- Get any laptop dual GPUs using PRIME
- Make sure runtime PM is enabled for amdgpu
- Boot the machine
- If the machine managed to boot without hanging, switch out of X to
another VT. This should definitely cause X to hang infinitely.
Changes since v1:
- add appropriate #ifdef checks for CONFIG_PM. This is not very
useful, but it appears some kernel test suites test compiling amdgpu
with CONFIG_PM disabled, which results in this patch breaking the builds
if we don't include this #ifdef
Cc: stable@vger.kernel.org
Cc: Alex Deucher <alexdeucher@gmail.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Lyude <cpaul@redhat.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
If we do it at enable time, it's too late for the feature
checks.
v2: drop .init setting as per Peter's comments
bug: https://bugzilla.kernel.org/show_bug.cgi?id=115321
Reviewed-by: Peter Wu <peter@lekensteyn.nl>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: Peter Wu <peter@lekensteyn.nl>
If we do it at enable time, it's too late for the feature
checks.
v2: drop .init setting as per Peter's comments
Reviewed-by: Peter Wu <peter@lekensteyn.nl>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: Peter Wu <peter@lekensteyn.nl>
Pull CIFS/SMB3 fixes from Steve French:
"Various CIFS/SMB3 fixes, most for stable"
* 'for-next' of git://git.samba.org/sfrench/cifs-2.6:
CIFS: Fix a possible invalid memory access in smb2_query_symlink()
fs/cifs: make share unaccessible at root level mountable
cifs: fix crash due to race in hmac(md5) handling
cifs: unbreak TCP session reuse
cifs: Check for existing directory when opening file with O_CREAT
Add MF-Symlinks support for SMB 2.0
For PMD aligned (8M) hugepages, we currently allocate
all four page table levels which is wasteful. We now
allocate till PMD level only which saves memory usage
from page tables.
Also, when freeing page table for 8M hugepage backed region,
make sure we don't try to access non-existent PTE level.
Orabug: 22630259
Signed-off-by: Nitin Gupta <nitin.m.gupta@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change "Warning" to "warning" to make it look more like a GCC warning.
Hopefully that will be enough to help the 0-day bot or other automated
tools catch this warning earlier before it ends up in Linus's tree.
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/b1669f391a5db91040427fd9f8e1e79db18f9709.1469751119.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This fixes the following warning:
Warning: objtool: x86 instruction decoder differs from kernel
Unfortunately we have three identical copies of the x86 instruction
decoder in the kernel tree that have to be manually kept in sync.
It's on my TODO list to at least library-ize the ones in the tools
subdir so we'd only have two of them instead of three. In the meantime,
here's another manual sync.
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: c61f4d5eba ("perf tools: Add AVX-512 support to the instruction decoder used by Intel PT")
Link: http://lkml.kernel.org/r/d7f74b4d91fed25b0be33cd5c86f5131fa1a7529.1469751119.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This fixes some false positive objtool warnings seen with gcc 6.1.1:
kernel/trace/ring_buffer.o: warning: objtool: ring_buffer_read_page()+0x36c: sibling call from callable instruction with changed frame pointer
arch/x86/kernel/reboot.o: warning: objtool: native_machine_emergency_restart()+0x139: sibling call from callable instruction with changed frame pointer
lib/xz/xz_dec_stream.o: warning: objtool: xz_dec_run()+0xc2: sibling call from callable instruction with changed frame pointer
With GCC 6, a new code pattern is sometimes used to access a switch
statement jump table in .rodata, which objtool doesn't yet recognize:
mov [rodata addr],%reg1
... some instructions ...
jmpq *(%reg1,%reg2,8)
Add support for detecting that pattern. The detection code is rather
crude, but it's still effective at weeding out false positives and
catching real warnings. It can be refined later once objtool starts
reading DWARF CFI.
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/b8c9503b4ad8c8a827cc5400db4c1b40a3ea07bc.1469751119.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
- Fix the tools/vm/ build by making libapi provide the str_error_c function,
that libapi uses but wasn't part of the list of objects linked with
tools/vm/ programs. (Arnaldo Carvalho de Melo)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Merge tag 'perf-urgent-for-mingo-20160728' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent
Pull perf/urgent fix from Arnaldo Carvalho de Melo:
- Fix the tools/vm/ build by making libapi provide the str_error_c function,
that libapi uses but wasn't part of the list of objects linked with
tools/vm/ programs. (Arnaldo Carvalho de Melo)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
FUSE_HAS_IOCTL_DIR should be assigned to ->flags, it may be a typo.
Signed-off-by: Wei Fang <fangwei1@huawei.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Fixes: 69fe05c90e ("fuse: add missing INIT flags")
Cc: <stable@vger.kernel.org>
fuse_flush() calls write_inode_now() that triggers writeback, but actual
writeback will happen later, on fuse_sync_writes(). If an error happens,
fuse_writepage_end() will set error bit in mapping->flags. So, we have to
check mapping->flags after fuse_sync_writes().
Signed-off-by: Maxim Patlasov <mpatlasov@virtuozzo.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Fixes: 4d99ff8f12 ("fuse: Turn writeback cache on")
Cc: <stable@vger.kernel.org> # v3.15+
Due to implementation of fuse writeback filemap_write_and_wait_range() does
not catch errors. We have to do this directly after fuse_sync_writes()
Signed-off-by: Alexey Kuznetsov <kuznet@virtuozzo.com>
Signed-off-by: Maxim Patlasov <mpatlasov@virtuozzo.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Fixes: 4d99ff8f12 ("fuse: Turn writeback cache on")
Cc: <stable@vger.kernel.org> # v3.15+
In kernel bug 150021, a kernel panic was reported when restoring a
hibernate image. Only a picture of the oops was reported, so I can't
paste the whole thing here. But here are the most interesting parts:
kernel tried to execute NX-protected page - exploit attempt? (uid: 0)
BUG: unable to handle kernel paging request at ffff8804615cfd78
...
RIP: ffff8804615cfd78
RSP: ffff8804615f0000
RBP: ffff8804615cfdc0
...
Call Trace:
do_signal+0x23
exit_to_usermode_loop+0x64
...
The RIP is on the same page as RBP, so it apparently started executing
on the stack.
The bug was bisected to commit ef0f3ed5a4 (x86/asm/power: Create
stack frames in hibernate_asm_64.S), which in retrospect seems quite
dangerous, since that code saves and restores the stack pointer from a
global variable ('saved_context').
There are a lot of moving parts in the hibernate save and restore paths,
so I don't know exactly what caused the panic. Presumably, a FRAME_END
was executed without the corresponding FRAME_BEGIN, or vice versa. That
would corrupt the return address on the stack and would be consistent
with the details of the above panic.
[ rjw: One major problem is that by the time the FRAME_BEGIN in
restore_registers() is executed, the stack pointer value may not
be valid any more. Namely, the stack area pointed to by it
previously may have been overwritten by some image memory contents
and that page frame may now be used for whatever different purpose
it had been allocated for before hibernation. In that case, the
FRAME_BEGIN will corrupt that memory. ]
Instead of doing the frame pointer save/restore around the bounds of the
affected functions, just do it around the call to swsusp_save().
That has the same effect of ensuring that if swsusp_save() sleeps, the
frame pointers will be correct. It's also a much more obviously safe
way to do it than the original patch. And objtool still doesn't report
any warnings.
Fixes: ef0f3ed5a4 (x86/asm/power: Create stack frames in hibernate_asm_64.S)
Link: https://bugzilla.kernel.org/show_bug.cgi?id=150021
Cc: 4.6+ <stable@vger.kernel.org> # 4.6+
Reported-by: Andre Reinke <andre.reinke@mailbox.org>
Tested-by: Andre Reinke <andre.reinke@mailbox.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The IV output vectors should only be copied from the _complete operation
and not from the _process operation, i.e only from the operation that is
designed to copy the result of the request to the right location. This
copy is already done in the _complete operation, so this commit removes
the duplicated code in the _process op.
Fixes: 3610d6cd5231 ("crypto: marvell - Add a complete...")
Signed-off-by: Romain Perier <romain.perier@free-electrons.com>
Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
In mpi_read_raw_from_sgl we may leak the SG miter resouces after
reading the leading zeroes. This patch fixes this by stopping the
iteration once the leading zeroes have been read.
Fixes: 127827b9c2 ("lib/mpi: Do not do sg_virt")
Reported-by: Nicolai Stange <nicstange@gmail.com>
Tested-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The empty checking logic is duplicated in ovl_check_empty_and_clear() and
ovl_remove_and_whiteout(), except the condition for clearing whiteouts is
different:
ovl_check_empty_and_clear() checked for being upper
ovl_remove_and_whiteout() checked for merge OR lower
Move the intersection of those checks (upper AND merge) into
ovl_check_empty_and_clear() and simplify ovl_remove_and_whiteout().
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
This does not work and does not make sense. So instead of fixing it
(probably not hard) just disallow.
Reported-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Cc: <stable@vger.kernel.org>
Right now we remove MAY_WRITE/MAY_APPEND bits from mask if realfile is on
lower/. This is done as files on lower will never be written and will be
copied up. But to copy up a file, mounter should have MAY_READ permission
otherwise copy up will fail. So set MAY_READ in mask when MAY_WRITE is
reset.
Dan Walsh noticed this when he did access(lowerfile, W_OK) and it returned
True (context mounts) but when he tried to actually write to file, it
failed as mounter did not have permission on lower file.
[SzM] don't set MAY_READ if only MAY_APPEND is set without MAY_WRITE; this
won't trigger a copy-up.
Reported-by: Dan Walsh <dwalsh@redhat.com>
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Right now if file is on lower/, we remove MAY_WRITE/MAY_APPEND bits from
mask as lower/ will never be written and file will be copied up. But this
is not true for special files. These files are not copied up and are opened
in place. So don't dilute the checks for these types of files.
Reported-by: Dan Walsh <dwalsh@redhat.com>
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Setting POSIX ACL needs special handling:
1) Some permission checks are done by ->setxattr() which now uses mounter's
creds ("ovl: do operations on underlying file system in mounter's
context"). These permission checks need to be done with current cred as
well.
2) Setting ACL can fail for various reasons. We do not need to copy up in
these cases.
In the mean time switch to using generic_setxattr.
[Arnd Bergmann] Fix link error without POSIX ACL. posix_acl_from_xattr()
doesn't have a 'static inline' implementation when CONFIG_FS_POSIX_ACL is
disabled, and I could not come up with an obvious way to do it.
This instead avoids the link error by defining two sets of ACL operations
and letting the compiler drop one of the two at compile time depending
on CONFIG_FS_POSIX_ACL. This avoids all references to the ACL code,
also leading to smaller code.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Inode attributes are copied up to overlay inode (uid, gid, mode, atime,
mtime, ctime) so generic code using these fields works correcty. If a hard
link is created in overlayfs separate inodes are allocated for each link.
If chmod/chown/etc. is performed on one of the links then the inode
belonging to the other ones won't be updated.
This patch attempts to fix this by sharing inodes for hard links.
Use inode hash (with real inode pointer as a key) to make sure overlay
inodes are shared for hard links on upper. Hard links on lower are still
split (which is not user observable until the copy-up happens, see
Documentation/filesystems/overlayfs.txt under "Non-standard behavior").
The inode is only inserted in the hash if it is non-directoy and upper.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
To get from overlay inode to real inode we currently use 'struct
ovl_entry', which has lifetime connected to overlay dentry. This is okay,
since each overlay dentry had a new overlay inode allocated.
Following patch will break that assumption, so need to leave out ovl_entry.
This patch stores the real inode directly in i_private, with the lowest bit
used to indicate whether the inode is upper or lower.
Lifetime rules remain, using ovl_inode_real() must only be done while
caller holds ref on overlay dentry (and hence on real dentry), or within
RCU protected regions.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Fix atime update logic in overlayfs.
This patch adds an i_op->update_time() handler to overlayfs inodes. This
forwards atime updates to the upper layer only. No atime updates are done
on lower layers.
Remove implicit atime updates to underlying files and directories with
O_NOATIME. Remove explicit atime update in ovl_readlink().
Clear atime related mnt flags from cloned upper mount. This means atime
updates are controlled purely by overlayfs mount options.
Reported-by: Konstantin Khlebnikov <koct9i@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
When creating directory in workdir, the group/sgid inheritance from the
parent dir was omitted completely. Fix this by calling inode_init_owner()
on overlay inode and using the resulting uid/gid/mode to create the file.
Unfortunately the sgid bit can be stripped off due to umask, so need to
reset the mode in this case in workdir before moving the directory in
place.
Reported-by: Eryu Guan <eguan@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
The fact that we always do permission checking on the overlay inode and
clear MAY_WRITE for checking access to the lower inode allows cruft to be
removed from ovl_permission().
1) "default_permissions" option effectively did generic_permission() on the
overlay inode with i_mode, i_uid and i_gid updated from underlying
filesystem. This is what we do by default now. It did the update using
vfs_getattr() but that's only needed if the underlying filesystem can
change (which is not allowed). We may later introduce a "paranoia_mode"
that verifies that mode/uid/gid are not changed.
2) splitting out the IS_RDONLY() check from inode_permission() also becomes
unnecessary once we remove the MAY_WRITE from the lower inode check.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Now we have two levels of checks in ovl_permission(). overlay inode
is checked with the creds of task while underlying inode is checked
with the creds of mounter.
Looks like mounter does not have to have WRITE access to files on lower/.
So remove the MAY_WRITE from access mask for checks on underlying
lower inode.
This means task should still have the MAY_WRITE permission on lower
inode and mounter is not required to have MAY_WRITE.
It also solves the problem of read only NFS mounts being used as lower.
If __inode_permission(lower_inode, MAY_WRITE) is called on read only
NFS, it fails. By resetting MAY_WRITE, check succeeds and case of
read only NFS shold work with overlay without having to specify any
special mount options (default permission).
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
