linux/drivers/oprofile, branch v3.11

drivers: delete __cpuinit usage from all remaining drivers files

2013-07-14T23:36:59Z

The __cpuinit type of throwaway sections might have made sense some time ago when RAM was more constrained, but now the savings do not offset the cost and complications. For example, the fix in commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time") is a good example of the nasty type of bugs that can be created with improper use of the various __init prefixes. After a discussion on LKML[1] it was decided that cpuinit should go the way of devinit and be phased out. Once all the users are gone, we can then finally remove the macros themselves from linux/init.h. This removes all the remaining one-off uses of the __cpuinit macros from all C files in the drivers/* directory. [1] https://lkml.org/lkml/2013/5/20/589 Cc: Greg Kroah-Hartman Acked-by: Greg Kroah-Hartman Signed-off-by: Paul Gortmaker

fs: Limit sys_mount to only request filesystem modules.

2013-03-04T03:36:31Z

Modify the request_module to prefix the file system type with "fs-" and add aliases to all of the filesystems that can be built as modules to match. A common practice is to build all of the kernel code and leave code that is not commonly needed as modules, with the result that many users are exposed to any bug anywhere in the kernel. Looking for filesystems with a fs- prefix limits the pool of possible modules that can be loaded by mount to just filesystems trivially making things safer with no real cost. Using aliases means user space can control the policy of which filesystem modules are auto-loaded by editing /etc/modprobe.d/*.conf with blacklist and alias directives. Allowing simple, safe, well understood work-arounds to known problematic software. This also addresses a rare but unfortunate problem where the filesystem name is not the same as it's module name and module auto-loading would not work. While writing this patch I saw a handful of such cases. The most significant being autofs that lives in the module autofs4. This is relevant to user namespaces because we can reach the request module in get_fs_type() without having any special permissions, and people get uncomfortable when a user specified string (in this case the filesystem type) goes all of the way to request_module. After having looked at this issue I don't think there is any particular reason to perform any filtering or permission checks beyond making it clear in the module request that we want a filesystem module. The common pattern in the kernel is to call request_module() without regards to the users permissions. In general all a filesystem module does once loaded is call register_filesystem() and go to sleep. Which means there is not much attack surface exposed by loading a filesytem module unless the filesystem is mounted. In a user namespace filesystems are not mounted unless .fs_flags = FS_USERNS_MOUNT, which most filesystems do not set today. Acked-by: Serge Hallyn Acked-by: Kees Cook Reported-by: Kees Cook Signed-off-by: "Eric W. Biederman"

oprofilefs: add missing ->i_mutex locking in object creation

2013-02-23T04:31:38Z

Right now it's safe only during initial mount *and* functions are asking to be abused for dynamic adding of objects. Signed-off-by: Al Viro

mm: use mm->exe_file instead of first VM_EXECUTABLE vma->vm_file

2012-10-09T07:22:18Z

Some security modules and oprofile still uses VM_EXECUTABLE for retrieving a task's executable file. After this patch they will use mm->exe_file directly. mm->exe_file is protected with mm->mmap_sem, so locking stays the same. Signed-off-by: Konstantin Khlebnikov Acked-by: Chris Metcalf [arch/tile] Acked-by: Tetsuo Handa [tomoyo] Cc: Alexander Viro Cc: Carsten Otte Cc: Cyrill Gorcunov Cc: Eric Paris Cc: H. Peter Anvin Cc: Hugh Dickins Cc: Ingo Molnar Acked-by: James Morris Cc: Jason Baron Cc: Kentaro Takeda Cc: Matt Helsley Cc: Nick Piggin Cc: Oleg Nesterov Cc: Peter Zijlstra Cc: Robert Richter Cc: Suresh Siddha Cc: Venkatesh Pallipadi Acked-by: Linus Torvalds Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

oprofile: Remove 'WQ on CPUx, prefer CPUy' warning

2012-08-27T12:49:39Z

Under certain workloads we see the following warnings: WQ on CPU0, prefer CPU1 WQ on CPU0, prefer CPU2 WQ on CPU0, prefer CPU3 It warns the user that the wq to access a per-cpu buffers runs not on the same cpu. This happens if the wq is rescheduled on a different cpu than where the buffer is located. This was probably implemented to detect performance issues. Not sure if there actually is one as the buffers are copied to a single buffer anyway which should be the actual bottleneck. We wont change WQ implementation. Since a user can do nothing the warning is pointless. Removing it. Cc: Andi Kleen Signed-off-by: Robert Richter

oprofile, perf: Use per-cpu framework

2012-06-22T14:31:20Z

This changes oprofile_perf.c to use the per-cpu framework. Using the per-cpu framework should avoid error like the following: arch/arm/oprofile/../../../drivers/oprofile/oprofile_perf.c:28:28: error: variably modified 'perf_events' at file scope Reported-by: William Cohen Cc: Will Deacon Signed-off-by: Robert Richter

oprofile: perf: use NR_CPUS instead or nr_cpumask_bits for static array

2012-06-21T14:15:11Z

The OProfile perf backend uses a static array to keep track of the perf events on the system. When compiling with CONFIG_CPUMASK_OFFSTACK=y && SMP, nr_cpumask_bits is not a compile-time constant and the build will fail with: oprofile_perf.c:28: error: variably modified 'perf_events' at file scope This patch uses NR_CPUs instead of nr_cpumask_bits for the array initialisation. If this causes space problems in the future, we can always move to dynamic allocation for the events array. Cc: Matt Fleming Reported-by: Russell King - ARM Linux Signed-off-by: Will Deacon Cc: # v2.6.37+ Signed-off-by: Robert Richter

simple_open: automatically convert to simple_open()

2012-04-05T22:25:50Z

Many users of debugfs copy the implementation of default_open() when they want to support a custom read/write function op. This leads to a proliferation of the default_open() implementation across the entire tree. Now that the common implementation has been consolidated into libfs we can replace all the users of this function with simple_open(). This replacement was done with the following semantic patch: @ open @ identifier open_f != simple_open; identifier i, f; @@ -int open_f(struct inode *i, struct file *f) -{ ( -if (i->i_private) -f->private_data = i->i_private; | -f->private_data = i->i_private; ) -return 0; -} @ has_open depends on open @ identifier fops; identifier open.open_f; @@ struct file_operations fops = { ... -.open = open_f, +.open = simple_open, ... }; [akpm@linux-foundation.org: checkpatch fixes] Signed-off-by: Stephen Boyd Cc: Greg Kroah-Hartman Cc: Al Viro Cc: Julia Lawall Acked-by: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

tidy up after d_make_root() conversion

2012-03-21T01:29:37Z

Signed-off-by: Al Viro

switch open-coded instances of d_make_root() to new helper

2012-03-21T01:29:35Z

Signed-off-by: Al Viro