Blacklisting a module in linux has long been a problem. The current
procedure is to use rd.blacklist=module_name, however, that doesn't
cover the case after the initramfs and before a boot prompt (where one
is supposed to use /etc/modprobe.d/blacklist.conf to blacklist
runtime loading). Using rd.shell to get an early prompt is hit-or-miss,
and doesn't cover all situations AFAICT.
This patch adds this functionality of permanently blacklisting a module
by its name via the kernel parameter module_blacklist=module_name.
[v2]: Rusty, use core_param() instead of __setup() which simplifies
things.
[v3]: Rusty, undo wreckage from strsep()
[v4]: Rusty, simpler version of blacklisted()
Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: linux-doc@vger.kernel.org
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
When running with lockdep enabled, I triggered the WARN_ON() in the
module code that asserts when module_mutex or rcu_read_lock_sched are
not held. The issue I have is that this can also be called from the
dump_stack() code, causing us to enter an infinite loop...
------------[ cut here ]------------
WARNING: CPU: 1 PID: 0 at kernel/module.c:268 module_assert_mutex_or_preempt+0x3c/0x3e
Modules linked in: ip6t_REJECT nf_reject_ipv6 nf_conntrack_ipv6
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.7.0-rc3-test-00013-g501c2375253c #14
Hardware name: MSI MS-7823/CSM-H87M-G43 (MS-7823), BIOS V1.6 02/22/2014
ffff880215e8fa70 ffff880215e8fa70 ffffffff812fc8e3 0000000000000000
ffffffff81d3e55b ffff880215e8fac0 ffffffff8104fc88 ffffffff8104fcab
0000000915e88300 0000000000000046 ffffffffa019b29a 0000000000000001
Call Trace:
[<ffffffff812fc8e3>] dump_stack+0x67/0x90
[<ffffffff8104fc88>] __warn+0xcb/0xe9
[<ffffffff8104fcab>] ? warn_slowpath_null+0x5/0x1f
------------[ cut here ]------------
WARNING: CPU: 1 PID: 0 at kernel/module.c:268 module_assert_mutex_or_preempt+0x3c/0x3e
Modules linked in: ip6t_REJECT nf_reject_ipv6 nf_conntrack_ipv6
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.7.0-rc3-test-00013-g501c2375253c #14
Hardware name: MSI MS-7823/CSM-H87M-G43 (MS-7823), BIOS V1.6 02/22/2014
ffff880215e8f7a0 ffff880215e8f7a0 ffffffff812fc8e3 0000000000000000
ffffffff81d3e55b ffff880215e8f7f0 ffffffff8104fc88 ffffffff8104fcab
0000000915e88300 0000000000000046 ffffffffa019b29a 0000000000000001
Call Trace:
[<ffffffff812fc8e3>] dump_stack+0x67/0x90
[<ffffffff8104fc88>] __warn+0xcb/0xe9
[<ffffffff8104fcab>] ? warn_slowpath_null+0x5/0x1f
------------[ cut here ]------------
WARNING: CPU: 1 PID: 0 at kernel/module.c:268 module_assert_mutex_or_preempt+0x3c/0x3e
Modules linked in: ip6t_REJECT nf_reject_ipv6 nf_conntrack_ipv6
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.7.0-rc3-test-00013-g501c2375253c #14
Hardware name: MSI MS-7823/CSM-H87M-G43 (MS-7823), BIOS V1.6 02/22/2014
ffff880215e8f4d0 ffff880215e8f4d0 ffffffff812fc8e3 0000000000000000
ffffffff81d3e55b ffff880215e8f520 ffffffff8104fc88 ffffffff8104fcab
0000000915e88300 0000000000000046 ffffffffa019b29a 0000000000000001
Call Trace:
[<ffffffff812fc8e3>] dump_stack+0x67/0x90
[<ffffffff8104fc88>] __warn+0xcb/0xe9
[<ffffffff8104fcab>] ? warn_slowpath_null+0x5/0x1f
------------[ cut here ]------------
WARNING: CPU: 1 PID: 0 at kernel/module.c:268 module_assert_mutex_or_preempt+0x3c/0x3e
[...]
Which gives us rather useless information. Worse yet, there's some race
that causes this, and I seldom trigger it, so I have no idea what
happened.
This would not be an issue if that warning was a WARN_ON_ONCE().
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
A regression is caused by the following commit:
Commit: 02b771b64b
Subject: ACPI / EC: Fix an issue caused by the serialized _Qxx evaluations
In this commit, using system workqueue causes that the maximum parallel
executions of _Qxx can exceed 255. This violates the method reentrancy
limit in ACPICA and generates the following error log:
ACPI Error: Method reached maximum reentrancy limit (255) (20150818/dsmethod-341)
This patch creates a seperate workqueue and limits the number of parallel
_Qxx evaluations down to a configurable value (can be tuned against number
of online CPUs).
Since EC events are handled after driver probe, we can create the workqueue
in acpi_ec_init().
Fixes: 02b771b64b (ACPI / EC: Fix an issue caused by the serialized _Qxx evaluations)
Link: https://bugzilla.kernel.org/show_bug.cgi?id=135691
Cc: 4.3+ <stable@vger.kernel.org> # 4.3+
Reported-and-tested-by: Helen Buus <ubuntu@hbuus.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Something made the sys_epoll_wait() function alias not to be found in
the vmlinux DWARF info, being found only in /proc/kallsyms, which made
the BPF perf tests to fail:
[root@jouet ~]# perf test BPF
37: Test BPF filter :
37.1: Test basic BPF filtering : FAILED!
37.2: Test BPF prologue generation : Skip
37.3: Test BPF relocation checker : Skip
[root@jouet ~]#
Using -v we can see it is failing to find DWARF info for the probed function,
sys_epoll_wait, which we can find in /proc/kallsyms but not in vmlinux with
CONFIG_DEBUG_INFO:
[root@jouet ~]# grep -w sys_epoll_wait /proc/kallsyms
ffffffffbd295b50 T sys_epoll_wait
[root@jouet ~]#
[root@jouet ~]# readelf -wi /lib/modules/4.7.0+/build/vmlinux | grep -w sys_epoll_wait
[root@jouet ~]#
If we try to use perf probe:
[root@jouet ~]# perf probe sys_epoll_wait
Failed to find debug information for address ffffffffbd295b50
Probe point 'sys_epoll_wait' not found.
Error: Failed to add events.
[root@jouet ~]#
It all works if we use SyS_epoll_wait, that is just an alias to the probed
function:
[root@jouet ~]# grep -i sys_epoll_wait /proc/kallsyms
ffffffffbd295b50 T SyS_epoll_wait
ffffffffbd295b50 T sys_epoll_wait
[root@jouet ~]#
So use it:
[root@jouet ~]# perf test BPF
37: Test BPF filter :
37.1: Test basic BPF filtering : Ok
37.2: Test BPF prologue generation : Ok
37.3: Test BPF relocation checker : Ok
[root@jouet ~]#
Further info:
[root@jouet ~]# gcc --version
gcc (GCC) 6.1.1 20160621 (Red Hat 6.1.1-3)
[acme@jouet linux]$ cat /etc/fedora-release
Fedora release 24 (Twenty Four)
Investigation as to why it fails is still underway, but it was always
going from sys_epoll_wait to SyS_epoll_wait when looking up the DWARF
info in vmlinux, and this is what is breaking now.
Switching to use SyS_epoll_wait allows this test to proceed and test the
BPF code it was designed for, so lets have this in to allow passing this
test while we fix the root cause.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-7hekjp0bodwjbb419sl2b55h@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
If CONFIG_TRANSPARENT_HUGE_PAGECACHE=n, HPAGE_PMD_NR evaluates to
BUILD_BUG_ON(), and may cause (e.g. with gcc 4.12):
mm/built-in.o: In function `shmem_alloc_hugepage':
shmem.c:(.text+0x17570): undefined reference to `__compiletime_assert_1365'
To fix this, move the assignment to hindex after the check for huge
pages support.
Fixes: 800d8c63b2 ("shmem: add huge pages support")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We can't pass error pointers to kfree() or it causes an oops.
Fixes: 52b209f7b8 ('get rid of hostfs_read_inode()')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
This adds support for kcov to UML.
There is a small problem where UML will randomly segfault during boot;
this is because current_thread_info() occasionally returns an invalid
(non-NULL) pointer and we try to dereference it in
__sanitizer_cov_trace_pc(). I consider this a bug in UML itself and this
patch merely exposes it.
[v2: disable instrumentation in UML-specific code]
Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Thomas Meyer <thomas@m3y3r.de>
Cc: user-mode-linux-devel <user-mode-linux-devel@lists.sourceforge.net>
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Instead proving its own arch_local_irq_save() and arch_irqs_disabled()
version use the generic version from asm-generic/irqflags.h.
A nice side effect is that um gets a few additional arch_ functions
as well.
Signed-off-by: Daniel Wagner <daniel.wagner@bmw-carit.de>
[rw: Massaged commit message]
Signed-off-by: Richard Weinberger <richard@nod.at>
We are in atomic context and must not sleep.
Sleeping here is possible since malloc() maps
to kmalloc() with GFP_KERNEL.
Cc: stable@vger.kernel.org
Fixes: b6024b21 ("um: extend fpstate to _xstate to support YMM registers")
Signed-off-by: Richard Weinberger <richard@nod.at>
This clearly had never gotten tested, probably because you need a fairly
minimal configuration in order to disable DEBUG_FS (several other
options select it).
The dummy inline functions that were used for the no-DEBUG_FS case were
missing the argument names in the declarations.
Fixes: 1dac891c1c ("drm/i915: Register debugfs interface last")
Reported-and-tested-by: Jörg Otte <jrg.otte@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently UML sets up physical memory very early,
long before setup_arch() was called by the kernel main
function.
This can cause problems when code paths in UML's memory setup
code assume that the kernel is already running.
i.e. when kmemleak is enabled it will evaluate current()
in free_bootmem(). That early current() is undefined and
UML explodes.
Solve the problem by setting up physical memory in setup_arch(),
at this stage the kernel has materialized and basic infrastructure
such as current() works.
Signed-off-by: Richard Weinberger <richard@nod.at>
alloc_bootmem function never returns NULL. Thus a NULL test after a
call to this function is unnecessary.
The Coccinelle semantic patch used to make this change is follows:
@@
expression E;
statement S;
@@
E =
alloc_bootmem(...)
... when != E
- if (E == NULL) S
Signed-off-by: Amitoj Kaur Chawla <amitoj1606@gmail.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
cgroup's document path is changed to "cgroup-v1". update it.
Signed-off-by: seokhoon.yoon <iamyooon@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Simply move the dochelp rule outside of the HAVE_SPHINX check,
overriding the .DEFAULT rule for HAVE_SPHINX=0.
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Christian Kujau <lists@nerdbynature.de>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Jeff Mahoney's cleanup commit (14a1e067b4) wasn't correct for csums on
machines where the pagesize >= metadata blocksize.
This just reverts the relevant hunks to bring the old math back.
Signed-off-by: Chris Mason <clm@fb.com>
. Move the suppressing of the __builtin_return_address >0 warning to the
tracing directory only.
. metag recordmcount fix for newer glibc's
. Two tracing histogram fixes that were reported by KASAN
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Merge tag 'trace-v4.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
"A few updates and fixes:
- move the suppressing of the __builtin_return_address >0 warning to
the tracing directory only.
- metag recordmcount fix for newer glibc's
- two tracing histogram fixes that were reported by KASAN"
* tag 'trace-v4.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Fix use-after-free in hist_register_trigger()
tracing: Fix use-after-free in hist_unreg_all/hist_enable_unreg_all
Makefile: Mute warning for __builtin_return_address(>0) for tracing only
ftrace/recordmcount: Work around for addition of metag magic but not relocations
With gcc < 4.2 (e.g. 4.1.2):
CC fs/proc/task_mmu.o
cc1: error: unrecognized command line option "-Wno-override-init"
To fix this, only enable the compiler option when it is actually
supported by the compiler.
Fixes: ca52953f5f ("fs/proc/task_mmu.c: suppress compilation warnings with W=1")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When lvm2 userspace requests a RaidLV repair, it sets the rebuild
constructor flag on the new replacement DataLVs but does not clear the
respective MetaLVs. Hence the superblock that is loaded from such new
MetaLVs may have a non-zero incompat_features member and the constructor
will fail with false-positive on incompat_features.
Solve by initializing the incompat_features member properly.
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
In v9fs_vfs_rename() we need to clone the parents' fids, not just
find them.
Spotted-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
__CTR_FLAG_MIN_RECOVERY_RATE was used instead of __CTR_FLAG_MAX_RECOVERY_RATE
thus causing max_recovery_rate to be rejected in case min_recovery_rate
was already set.
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
krealloc() doesn't work always properly with __GFP_ZERO flag as
expected. For clearing the reallocated area, we need to clear
explicitly instead.
Reported-by: Joe Perches <joe@perches.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
file_remove_privs() is called with inode lock on file_inode(), which
proceeds to calling notify_change() on file->f_path.dentry. Which triggers
the WARN_ON_ONCE(!inode_is_locked(inode)) in addition to deadlocking later
when ovl_setattr tries to lock the underlying inode again.
Fix this mess by not mixing the layers, but doing everything on underlying
dentry/inode.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Fixes: 07a2daab49 ("ovl: Copy up underlying inode's ->i_mode to overlay inode")
Cc: <stable@vger.kernel.org>
This is a driver for SiS 9200 family touchscreen controllers using I2C bus.
Signed-off-by: Mika Penttilä <mika.penttila@nextfour.com>
Acked-by: Tammy Tseng <tammy_tseng@sis.com>
Acked-by: Yuger Yu <yuger_yu@sis.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
When using clang as HOSTCC, the following warnings appear:
In file included from arch/mips/boot/tools/relocs_64.c:27:0:
arch/mips/boot/tools/relocs.c: In function ‘read_relocs’:
arch/mips/boot/tools/relocs.c:397:4: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing]
ELF_R_SYM(rel->r_info) = elf32_to_cpu(ELF_R_SYM(rel->r_info));
^~~~~~~~~
arch/mips/boot/tools/relocs.c:397:4: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing]
arch/mips/boot/tools/relocs.c: In function ‘walk_relocs’:
arch/mips/boot/tools/relocs.c:491:4: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing]
Elf_Sym *sym = &sh_symtab[ELF_R_SYM(rel->r_info)];
^~~~~~~
arch/mips/boot/tools/relocs.c: In function ‘do_reloc’:
arch/mips/boot/tools/relocs.c:502:2: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing]
unsigned r_type = ELF_R_TYPE(rel->r_info);
^~~~~~~~
arch/mips/boot/tools/relocs.c: In function ‘do_reloc_info’:
arch/mips/boot/tools/relocs.c:641:3: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing]
rel_type(ELF_R_TYPE(rel->r_info)),
^~~~~~~~
Fix them by making Elf64_Mips_Rela a union
Signed-off-by: Harvey Hunt <harvey.hunt@imgtec.com>
Acked-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/13683/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
"calibrate" attribute does not provide "show" methods and thus we should
not mark it as readable.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Some ASUS laptops were shipped with touchpads that require to be woken up
first, before trying to switch them into absolute reporting mode, otherwise
touchpad would fail to work while flooding the logs with:
elan_i2c i2c-ELAN1000:00: invalid report id data (1)
Among affected devices are Asus E202SA, N552VW, X456UF, UX305CA, and
others. We detect such devices by checking the IC type and product ID
numbers and adjusting order of operations accordingly.
Signed-off-by: KT Liao <kt.liao@emc.com.tw>
Reported-by: Chris Chiu <chiu@endlessm.com>
Reported-by: Vlad Glagolev <stealth@vaygr.net>
Tested-by: Vlad Glagolev <stealth@vaygr.net>
Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
This driver adds support for Silead touchscreens. It has been tested
with GSL1680 and GSL3680 touch panels.
It supports ACPI and device tree enumeration. Screen resolution,
the maximum number of fingers supported and firmware name are
configurable.
Signed-off-by: Robert Dolca <robert.dolca@intel.com>
Signed-off-by: Daniel Jansen <djaniboe@gmail.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
The use of mixed psmouse_printk() and printk creates 2 lines in the log,
while the use of %*ph solves everything.
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Some configs of mips like xway_defconffig are failing with the error:
arch/mips/lantiq/irq.c:209:2: error: initialization from incompatible
pointer type [-Werror]
"icu",
^
arch/mips/lantiq/irq.c:209:2: error: (near initialization for
'ltq_irq_type.parent_device') [-Werror]
arch/mips/lantiq/irq.c:219:2: error: initialization from incompatible
pointer type [-Werror]
"eiu",
^
arch/mips/lantiq/irq.c:219:2: error: (near initialization for
'ltq_eiu_type.parent_device') [-Werror]
The first member of the "struct irq" is no longer a pointer for the
name.
Fixes: be45beb2df ("genirq: Add runtime power management support for IRQ chips")
Signed-off-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>
Acked-by: John Crispin <john@phrozen.org>
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/13684/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Commit 9402c68461 ("powerpc: Factor do_feature_fixup calls")
introduced a subtle bug on 32-bit. When reading the cpu spec from the
global, we not only need to do a pointer relocation on the global
address but also on the pointer we read from it.
This fixes crashes reported on MPC5200 based machines.
Fixes: 9402c68461 ("powerpc: Factor do_feature_fixup calls")
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The original code used a LRU list to evict nodes which were least
recently used. For correctness the evict code was moved under the
handler->lock, now add back the LRU list.
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Dean Luick <dean.luick@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
During an unexpected shutdown, references to tid_rb_node were NULL'ed out
without properly being released.
Fix this by calling clear_tid_node in the mmu notifier remove callback
rather than after these callbacks are called.
Reviewed-by: Dean Luick <dean.luick@intel.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
The reworked mmu_rb interface allows the unused mm argument to be removed.
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Dean Luick <dean.luick@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
The ops->remove() callback was called by hfi1_mmu_unregister() with a
NULL mm argument while holding a spinlock. In the case of sdma_rb_remove()
this caused it to pass current->mm to hfi1_release_user_pages()
This had 2 problems. First this would attempt to acquire the mmap_sem
under a spin lock. Second the use of current->mm is not always guaranteed
to be the proper mm when the fd is being closed.
Rather than depend on this implicit behavior we move all calls to
ops->remove outside of the spinlock. This also allows the correct
mm to be used in the remove callback without fear of deadlock.
Because the MMU notifier is not guaranteed to hold mm->mmap_sem, but
usually does, we must delay all remove callbacks until out of the notifier,
when the callbacks can take the mmap_sem if they need to.
Code comments were added to clarify what the expectations are for the
users of the mmu rb tree.
Suggested-by: Jim Foraker <foraker1@llnl.gov>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Dean Luick <dean.luick@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Use the new cache evict operation in the SDMA code. This allows the cache
to properly coordinate evicts and removes, preventing any race. With this
change, the separate list, lock, and race flag are not needed.
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Dean Luick <dean.luick@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Allow users to clear nodes from the rb tree based on their evict callback.
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Dean Luick <dean.luick@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Per file descriptor TID caching actions depend on a global that can
change midway through the lifetime of that file descriptor.
Make the use of caching consistent for the life of the file descriptor
by using the presence of the cache handler to decide when to use the cache
functions.
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Dean Luick <dean.luick@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Prarit Bhargava