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2017-07-15Merge branch 'work.mount' of ↵Linus Torvalds3-4/+15
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull ->s_options removal from Al Viro: "Preparations for fsmount/fsopen stuff (coming next cycle). Everything gets moved to explicit ->show_options(), killing ->s_options off + some cosmetic bits around fs/namespace.c and friends. Basically, the stuff needed to work with fsmount series with minimum of conflicts with other work. It's not strictly required for this merge window, but it would reduce the PITA during the coming cycle, so it would be nice to have those bits and pieces out of the way" * 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: isofs: Fix isofs_show_options() VFS: Kill off s_options and helpers orangefs: Implement show_options 9p: Implement show_options isofs: Implement show_options afs: Implement show_options affs: Implement show_options befs: Implement show_options spufs: Implement show_options bpf: Implement show_options ramfs: Implement show_options pstore: Implement show_options omfs: Implement show_options hugetlbfs: Implement show_options VFS: Don't use save/replace_mount_options if not using generic_show_options VFS: Provide empty name qstr VFS: Make get_filesystem() return the affected filesystem VFS: Clean up whitespace in fs/namespace.c and fs/super.c Provide a function to create a NUL-terminated string from unterminated data
2017-07-06pstore: Implement show_optionsDavid Howells3-4/+15
Implement the show_options superblock op for pstore as part of a bid to get rid of s_options and generic_show_options() to make it easier to implement a context-based mount where the mount options can be passed individually over a file descriptor. Signed-off-by: David Howells <dhowells@redhat.com> cc: Kees Cook <keescook@chromium.org> cc: Anton Vorontsov <anton@enomsg.org> cc: Colin Cross <ccross@android.com> cc: Tony Luck <tony.luck@intel.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-06-27pstore: use memdup_userGeliang Tang1-7/+4
Use memdup_user() helper instead of open-coding to simplify the code. Signed-off-by: Geliang Tang <geliangtang@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org>
2017-05-31pstore: Fix format string to use %u for record idKees Cook1-11/+11
The format string for record->id (u64) was using %lld instead of %llu. Signed-off-by: Kees Cook <keescook@chromium.org>
2017-05-31pstore: Populate pstore record->time fieldKees Cook2-11/+11
The current time will be initially available in the record->time field for all pstore_read() and pstore_write() calls. Backends can either update the field during read(), or use the field during write() instead of fetching time themselves. Signed-off-by: Kees Cook <keescook@chromium.org>
2017-05-31pstore: Create common record initializerKees Cook3-19/+28
In preparation for setting timestamps in the pstore core, create a common initializer routine, instead of using static initializers. Signed-off-by: Kees Cook <keescook@chromium.org>
2017-05-31pstore: Avoid potential infinite loopKees Cook1-2/+6
If a backend does not correctly iterate through its records, pstore will get stuck loading entries. Detect this with a large record count, and announce if we ever hit the limit. This will let future backend reading bugs less annoying to debug. Additionally adjust the error about pstore_mkfile() failing. Signed-off-by: Kees Cook <keescook@chromium.org>
2017-05-31pstore: Fix leaked pstore_record in pstore_get_backend_records()Douglas Anderson1-1/+3
When the "if (record->size <= 0)" test is true in pstore_get_backend_records() it's pretty clear that nobody holds a reference to the allocated pstore_record, yet we don't free it. Let's free it. Fixes: 2a2b0acf768c ("pstore: Allocate records on heap instead of stack") Signed-off-by: Douglas Anderson <dianders@chromium.org> Signed-off-by: Kees Cook <keescook@chromium.org> Cc: stable@vger.kernel.org
2017-05-31pstore: Don't warn if data is uncompressed and type is not PSTORE_TYPE_DMESGAnkit Kumar1-1/+4
commit 9abdcccc3d5f ("pstore: Extract common arguments into structure") moved record decompression to function. decompress_record() gets called without checking type and compressed flag. Warning will be reported if data is uncompressed. Pstore type PSTORE_TYPE_PPC_OPAL, PSTORE_TYPE_PPC_COMMON doesn't contain compressed data and warning get printed part of dmesg. Partial dmesg log: [ 35.848914] pstore: ignored compressed record type 6 [ 35.848927] pstore: ignored compressed record type 8 Above warning should not get printed as it is known that data won't be compressed for above type and it is valid condition. This patch returns if data is not compressed and print warning only if data is compressed and type is not PSTORE_TYPE_DMESG. Reported-by: Anton Blanchard <anton@au1.ibm.com> Signed-off-by: Ankit Kumar <ankit@linux.vnet.ibm.com> Reviewed-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Kees Cook <keescook@chromium.org> Fixes: 9abdcccc3d5f ("pstore: Extract common arguments into structure") Cc: stable@vger.kernel.org
2017-05-10Merge tag 'hwparam-20170420' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs Pull hw lockdown support from David Howells: "Annotation of module parameters that configure hardware resources including ioports, iomem addresses, irq lines and dma channels. This allows a future patch to prohibit the use of such module parameters to prevent that hardware from being abused to gain access to the running kernel image as part of locking the kernel down under UEFI secure boot conditions. Annotations are made by changing: module_param(n, t, p) module_param_named(n, v, t, p) module_param_array(n, t, m, p) to: module_param_hw(n, t, hwtype, p) module_param_hw_named(n, v, t, hwtype, p) module_param_hw_array(n, t, hwtype, m, p) where the module parameter refers to a hardware setting hwtype specifies the type of the resource being configured. This can be one of: ioport Module parameter configures an I/O port iomem Module parameter configures an I/O mem address ioport_or_iomem Module parameter could be either (runtime set) irq Module parameter configures an I/O port dma Module parameter configures a DMA channel dma_addr Module parameter configures a DMA buffer address other Module parameter configures some other value Note that the hwtype is compile checked, but not currently stored (the lockdown code probably won't require it). It is, however, there for future use. A bonus is that the hwtype can also be used for grepping. The intention is for the kernel to ignore or reject attempts to set annotated module parameters if lockdown is enabled. This applies to options passed on the boot command line, passed to insmod/modprobe or direct twiddling in /sys/module/ parameter files. The module initialisation then needs to handle the parameter not being set, by (1) giving an error, (2) probing for a value or (3) using a reasonable default. What I can't do is just reject a module out of hand because it may take a hardware setting in the module parameters. Some important modules, some ipmi stuff for instance, both probe for hardware and allow hardware to be manually specified; if the driver is aborts with any error, you don't get any ipmi hardware. Further, trying to do this entirely in the module initialisation code doesn't protect against sysfs twiddling. [!] Note that in and of itself, this series of patches should have no effect on the the size of the kernel or code execution - that is left to a patch in the next series to effect. It does mark annotated kernel parameters with a KERNEL_PARAM_FL_HWPARAM flag in an already existing field" * tag 'hwparam-20170420' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs: (38 commits) Annotate hardware config module parameters in sound/pci/ Annotate hardware config module parameters in sound/oss/ Annotate hardware config module parameters in sound/isa/ Annotate hardware config module parameters in sound/drivers/ Annotate hardware config module parameters in fs/pstore/ Annotate hardware config module parameters in drivers/watchdog/ Annotate hardware config module parameters in drivers/video/ Annotate hardware config module parameters in drivers/tty/ Annotate hardware config module parameters in drivers/staging/vme/ Annotate hardware config module parameters in drivers/staging/speakup/ Annotate hardware config module parameters in drivers/staging/media/ Annotate hardware config module parameters in drivers/scsi/ Annotate hardware config module parameters in drivers/pcmcia/ Annotate hardware config module parameters in drivers/pci/hotplug/ Annotate hardware config module parameters in drivers/parport/ Annotate hardware config module parameters in drivers/net/wireless/ Annotate hardware config module parameters in drivers/net/wan/ Annotate hardware config module parameters in drivers/net/irda/ Annotate hardware config module parameters in drivers/net/hamradio/ Annotate hardware config module parameters in drivers/net/ethernet/ ...
2017-04-27pstore: Solve lockdep warning by moving inode locksKees Cook3-16/+36
Lockdep complains about a possible deadlock between mount and unlink (which is technically impossible), but fixing this improves possible future multiple-backend support, and keeps locking in the right order. The lockdep warning could be triggered by unlinking a file in the pstore filesystem: -> #1 (&sb->s_type->i_mutex_key#14){++++++}: lock_acquire+0xc9/0x220 down_write+0x3f/0x70 pstore_mkfile+0x1f4/0x460 pstore_get_records+0x17a/0x320 pstore_fill_super+0xa4/0xc0 mount_single+0x89/0xb0 pstore_mount+0x13/0x20 mount_fs+0xf/0x90 vfs_kern_mount+0x66/0x170 do_mount+0x190/0xd50 SyS_mount+0x90/0xd0 entry_SYSCALL_64_fastpath+0x1c/0xb1 -> #0 (&psinfo->read_mutex){+.+.+.}: __lock_acquire+0x1ac0/0x1bb0 lock_acquire+0xc9/0x220 __mutex_lock+0x6e/0x990 mutex_lock_nested+0x16/0x20 pstore_unlink+0x3f/0xa0 vfs_unlink+0xb5/0x190 do_unlinkat+0x24c/0x2a0 SyS_unlinkat+0x16/0x30 entry_SYSCALL_64_fastpath+0x1c/0xb1 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&sb->s_type->i_mutex_key#14); lock(&psinfo->read_mutex); lock(&sb->s_type->i_mutex_key#14); lock(&psinfo->read_mutex); Reported-by: Marta Lofstedt <marta.lofstedt@intel.com> Reported-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: Namhyung Kim <namhyung@kernel.org>
2017-04-27pstore: Remove unused vmalloc.h in pmsgGeliang Tang1-1/+0
Since the vmalloc code has been removed from write_pmsg() in the commit "5bf6d1b pstore/pmsg: drop bounce buffer", remove the unused header vmalloc.h. Signed-off-by: Geliang Tang <geliangtang@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org>
2017-04-20Annotate hardware config module parameters in fs/pstore/David Howells1-1/+1
When the kernel is running in secure boot mode, we lock down the kernel to prevent userspace from modifying the running kernel image. Whilst this includes prohibiting access to things like /dev/mem, it must also prevent access by means of configuring driver modules in such a way as to cause a device to access or modify the kernel image. To this end, annotate module_param* statements that refer to hardware configuration and indicate for future reference what type of parameter they specify. The parameter parser in the core sees this information and can skip such parameters with an error message if the kernel is locked down. The module initialisation then runs as normal, but just sees whatever the default values for those parameters is. Note that we do still need to do the module initialisation because some drivers have viable defaults set in case parameters aren't specified and some drivers support automatic configuration (e.g. PNP or PCI) in addition to manually coded parameters. This patch annotates drivers in fs/pstore/. Suggested-by: Alan Cox <gnomes@lxorguk.ukuu.org.uk> Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Kees Cook <keescook@chromium.org> cc: Anton Vorontsov <anton@enomsg.org> cc: Colin Cross <ccross@android.com> cc: Tony Luck <tony.luck@intel.com>
2017-03-07pstore: simplify write_user_compat()Kees Cook1-26/+20
Nothing actually uses write_user_compat() currently, but there is no reason to reuse the dmesg buffer. Instead, just allocate a new record buffer, copy in from userspace, and pass it to write() as normal. Signed-off-by: Kees Cook <keescook@chromium.org>
2017-03-07pstore: Remove write_buf() callbackKees Cook4-24/+29
Now that write() and write_buf() are functionally identical, this removes write_buf(), and renames write_buf_user() to write_user(). Additionally adds sanity-checks for pstore_info's declared functions and flags at registration time. Signed-off-by: Kees Cook <keescook@chromium.org>
2017-03-07pstore: Replace arguments for write_buf_user() APIKees Cook3-35/+23
Removes argument list in favor of pstore record, though the user buffer remains passed separately since it must carry the __user annotation. Signed-off-by: Kees Cook <keescook@chromium.org>
2017-03-07pstore: Replace arguments for write_buf() APIKees Cook3-33/+50
As with the other API updates, this removes the long argument list in favor of passing a single pstore recaord. Signed-off-by: Kees Cook <keescook@chromium.org>
2017-03-07pstore: Replace arguments for erase() APIKees Cook2-15/+12
This removes the argument list for the erase() callback and replaces it with a pointer to the backend record details to be removed. Signed-off-by: Kees Cook <keescook@chromium.org>
2017-03-07pstore: Do not duplicate record metadataKees Cook2-33/+30
This switches the inode-private data from carrying duplicate metadata to keeping the record passed in during pstore_mkfile(). Signed-off-by: Kees Cook <keescook@chromium.org>
2017-03-07pstore: Allocate records on heap instead of stackKees Cook1-8/+22
In preparation for handling records off to pstore_mkfile(), allocate the record instead of reusing stack. This still always frees the record, though, since pstore_mkfile() isn't yet keeping it. Signed-off-by: Kees Cook <keescook@chromium.org>
2017-03-07pstore: Pass record contents instead of copyingKees Cook2-11/+27
pstore_mkfile() shouldn't have to memcpy the record contents. It can use the existing copy instead. This adjusts the allocation lifetime management and renames the contents variable from "data" to "buf" to assist moving to struct pstore_record in the future. Signed-off-by: Kees Cook <keescook@chromium.org>
2017-03-07pstore: Always allocate buffer for decompressionKees Cook1-14/+24
Currently, pstore_mkfile() performs a memcpy() of the record contents, so it can live anywhere. However, this is needlessly wasteful. In preparation of pstore_mkfile() keeping the record contents, always allocate a buffer for the contents. Signed-off-by: Kees Cook <keescook@chromium.org>
2017-03-07pstore: Replace arguments for write() APIKees Cook1-27/+35
Similar to the pstore_info read() callback, there were too many arguments. This switches to the new struct pstore_record pointer instead. This adds "reason" and "part" to the record structure as well. Signed-off-by: Kees Cook <keescook@chromium.org>
2017-03-07pstore: Replace arguments for read() APIKees Cook2-30/+30
The argument list for the pstore_read() interface is unwieldy. This changes passes the new struct pstore_record instead. The erst backend was already doing something similar internally. Signed-off-by: Kees Cook <keescook@chromium.org>
2017-03-07pstore: Switch pstore_mkfile to pass recordKees Cook3-34/+34
Instead of the long list of arguments, just pass the new record struct. Signed-off-by: Kees Cook <keescook@chromium.org>
2017-03-07pstore: Move record decompression to functionKees Cook1-30/+37
This moves the record decompression logic out to a separate function to avoid the deep indentation. Signed-off-by: Kees Cook <keescook@chromium.org>
2017-03-07pstore: Extract common arguments into structureKees Cook1-25/+30
The read/mkfile pair pass the same arguments and should be cleared between calls. Move to a structure and wipe it after every loop. Signed-off-by: Kees Cook <keescook@chromium.org>
2017-03-07pstore: Improve register_pstore() error reportingKees Cook1-1/+5
Uncommon errors are better to get reported to dmesg so developers can more easily figure out why pstore is unhappy with a backend attempting to register. Signed-off-by: Kees Cook <keescook@chromium.org>
2017-03-07pstore: Avoid race in module unloadingKees Cook1-2/+2
Technically, it might be possible for struct pstore_info to go out of scope after the module_put(), so report the backend name first. Signed-off-by: Kees Cook <keescook@chromium.org>
2017-03-07pstore: Shut down worker when unregisteringKees Cook1-1/+9
When built as a module and running with update_ms >= 0, pstore will Oops during module unload since the work timer is still running. This makes sure the worker is stopped before unloading. Signed-off-by: Kees Cook <keescook@chromium.org> Cc: stable@vger.kernel.org
2017-03-07pstore: Use dynamic spinlock initializerKees Cook1-1/+1
The per-prz spinlock should be using the dynamic initializer so that lockdep can correctly track it. Without this, under lockdep, we get a warning at boot that the lock is in non-static memory. Fixes: 109704492ef6 ("pstore: Make spinlock per zone instead of global") Fixes: 76d5692a5803 ("pstore: Correctly initialize spinlock and flags") Signed-off-by: Kees Cook <keescook@chromium.org> Cc: stable@vger.kernel.org
2017-03-07pstore: constify pstore_zbackend structuresBhumika Goyal1-4/+4
The references of pstore_zbackend structures are stored into the pointer zbackend of type struct pstore_zbackend. The pointer zbackend can be made const as it is only dereferenced. After making this change the pstore_zbackend structures whose references are stored into the pointer zbackend can be made const too. File size before: text data bss dec hex filename 4817 541 172 5530 159a fs/pstore/platform.o File size after: text data bss dec hex filename 4865 477 172 5514 158a fs/pstore/platform.o Signed-off-by: Bhumika Goyal <bhumirks@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org>
2017-02-24fs/pstore: fs/squashfs: change usage of LZ4 to work with new LZ4 versionSven Schmidt1-9/+13
Update fs/pstore and fs/squashfs to use the updated functions from the new LZ4 module. Link: http://lkml.kernel.org/r/1486321748-19085-5-git-send-email-4sschmid@informatik.uni-hamburg.de Signed-off-by: Sven Schmidt <4sschmid@informatik.uni-hamburg.de> Cc: Bongkyu Kim <bongkyu.kim@lge.com> Cc: Rui Salvaterra <rsalvaterra@gmail.com> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: David S. Miller <davem@davemloft.net> Cc: Anton Vorontsov <anton@enomsg.org> Cc: Colin Cross <ccross@android.com> Cc: Kees Cook <keescook@chromium.org> Cc: Tony Luck <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-13pstore: Check for prz allocation in walkerKees Cook1-2/+3
Instead of needing additional checks in callers for unallocated przs, perform the check in the walker, which gives us a more universal way to handle the situation. Signed-off-by: Kees Cook <keescook@chromium.org>
2017-02-13pstore: Correctly initialize spinlock and flagsKees Cook1-5/+7
The ram backend wasn't always initializing its spinlock correctly. Since it was coming from kzalloc memory, though, it was harmless on architectures that initialize unlocked spinlocks to 0 (at least x86 and ARM). This also fixes a possibly ignored flag setting too. When running under CONFIG_DEBUG_SPINLOCK, the following Oops was visible: [ 0.760836] persistent_ram: found existing buffer, size 29988, start 29988 [ 0.765112] persistent_ram: found existing buffer, size 30105, start 30105 [ 0.769435] persistent_ram: found existing buffer, size 118542, start 118542 [ 0.785960] persistent_ram: found existing buffer, size 0, start 0 [ 0.786098] persistent_ram: found existing buffer, size 0, start 0 [ 0.786131] pstore: using zlib compression [ 0.790716] BUG: spinlock bad magic on CPU#0, swapper/0/1 [ 0.790729] lock: 0xffffffc0d1ca9bb0, .magic: 00000000, .owner: <none>/-1, .owner_cpu: 0 [ 0.790742] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.10.0-rc2+ #913 [ 0.790747] Hardware name: Google Kevin (DT) [ 0.790750] Call trace: [ 0.790768] [<ffffff900808ae88>] dump_backtrace+0x0/0x2bc [ 0.790780] [<ffffff900808b164>] show_stack+0x20/0x28 [ 0.790794] [<ffffff9008460ee0>] dump_stack+0xa4/0xcc [ 0.790809] [<ffffff9008113cfc>] spin_dump+0xe0/0xf0 [ 0.790821] [<ffffff9008113d3c>] spin_bug+0x30/0x3c [ 0.790834] [<ffffff9008113e28>] do_raw_spin_lock+0x50/0x1b8 [ 0.790846] [<ffffff9008a2d2ec>] _raw_spin_lock_irqsave+0x54/0x6c [ 0.790862] [<ffffff90083ac3b4>] buffer_size_add+0x48/0xcc [ 0.790875] [<ffffff90083acb34>] persistent_ram_write+0x60/0x11c [ 0.790888] [<ffffff90083aab1c>] ramoops_pstore_write_buf+0xd4/0x2a4 [ 0.790900] [<ffffff90083a9d3c>] pstore_console_write+0xf0/0x134 [ 0.790912] [<ffffff900811c304>] console_unlock+0x48c/0x5e8 [ 0.790923] [<ffffff900811da18>] register_console+0x3b0/0x4d4 [ 0.790935] [<ffffff90083aa7d0>] pstore_register+0x1a8/0x234 [ 0.790947] [<ffffff90083ac250>] ramoops_probe+0x6b8/0x7d4 [ 0.790961] [<ffffff90085ca548>] platform_drv_probe+0x7c/0xd0 [ 0.790972] [<ffffff90085c76ac>] driver_probe_device+0x1b4/0x3bc [ 0.790982] [<ffffff90085c7ac8>] __device_attach_driver+0xc8/0xf4 [ 0.790996] [<ffffff90085c4bfc>] bus_for_each_drv+0xb4/0xe4 [ 0.791006] [<ffffff90085c7414>] __device_attach+0xd0/0x158 [ 0.791016] [<ffffff90085c7b18>] device_initial_probe+0x24/0x30 [ 0.791026] [<ffffff90085c648c>] bus_probe_device+0x50/0xe4 [ 0.791038] [<ffffff90085c35b8>] device_add+0x3a4/0x76c [ 0.791051] [<ffffff90087d0e84>] of_device_add+0x74/0x84 [ 0.791062] [<ffffff90087d19b8>] of_platform_device_create_pdata+0xc0/0x100 [ 0.791073] [<ffffff90087d1a2c>] of_platform_device_create+0x34/0x40 [ 0.791086] [<ffffff900903c910>] of_platform_default_populate_init+0x58/0x78 [ 0.791097] [<ffffff90080831fc>] do_one_initcall+0x88/0x160 [ 0.791109] [<ffffff90090010ac>] kernel_init_freeable+0x264/0x31c [ 0.791123] [<ffffff9008a25bd0>] kernel_init+0x18/0x11c [ 0.791133] [<ffffff9008082ec0>] ret_from_fork+0x10/0x50 [ 0.793717] console [pstore-1] enabled [ 0.797845] pstore: Registered ramoops as persistent store backend [ 0.804647] ramoops: attached 0x100000@0xf7edc000, ecc: 0/0 Fixes: 663deb47880f ("pstore: Allow prz to control need for locking") Fixes: 109704492ef6 ("pstore: Make spinlock per zone instead of global") Reported-by: Brian Norris <briannorris@chromium.org> Signed-off-by: Kees Cook <keescook@chromium.org>
2017-02-09pstore: don't OOPS when there are no ftrace zonesBrian Norris1-1/+1
We'll OOPS in ramoops_get_next_prz() if the platform didn't ask for any ftrace zones (i.e., cxt->fprzs will be NULL). Let's just skip this entire FTRACE section if there's no 'fprzs'. Regression seen on a coreboot/depthcharge-based Chromebook. Fixes: 2fbea82bbb89 ("pstore: Merge per-CPU ftrace records into one") Cc: Joel Fernandes <joelaf@google.com> Cc: Kees Cook <keescook@chromium.org> Signed-off-by: Brian Norris <briannorris@chromium.org> Signed-off-by: Kees Cook <keescook@chromium.org>
2016-12-13Merge tag 'pstore-v4.10-rc1' of ↵Linus Torvalds6-126/+293
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull pstore updates from Kees Cook: "Improvements and fixes to pstore subsystem: - add additional checks for bad platform data - remove bounce buffer in console writer - protect read/unlink race with a mutex - correctly give up during dump locking failures - increase ftrace bandwidth by splitting ftrace buffers per CPU" * tag 'pstore-v4.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: ramoops: add pdata NULL check to ramoops_probe pstore: Convert console write to use ->write_buf pstore: Protect unlink with read_mutex pstore: Use global ftrace filters for function trace filtering ftrace: Provide API to use global filtering for ftrace ops pstore: Clarify context field przs as dprzs pstore: improve error report for failed setup pstore: Merge per-CPU ftrace records into one pstore: Add ftrace timestamp counter ramoops: Split ftrace buffer space into per-CPU zones pstore: Make ramoops_init_przs generic for other prz arrays pstore: Allow prz to control need for locking pstore: Warn on PSTORE_TYPE_PMSG using deprecated function pstore: Make spinlock per zone instead of global pstore: Actually give up during locking failure
2016-11-15ramoops: add pdata NULL check to ramoops_probeKees Cook1-2/+11
This adds a check for a NULL platform data, which should only be possible if a driver incorrectly sets up a probe request without also having defined the platform_data structure. This is based on a patch from Geliang Tang. Signed-off-by: Kees Cook <keescook@chromium.org>
2016-11-15pstore: Convert console write to use ->write_bufNamhyung Kim1-2/+2
Maybe I'm missing something, but I don't know why it needs to copy the input buffer to psinfo->buf and then write. Instead we can write the input buffer directly. The only implementation that supports console message (i.e. ramoops) already does it for ftrace messages. For the upcoming virtio backend driver, it needs to protect psinfo->buf overwritten from console messages. If it could use ->write_buf method instead of ->write, the problem will be solved easily. Cc: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Kees Cook <keescook@chromium.org>
2016-11-15pstore: Protect unlink with read_mutexNamhyung Kim1-2/+5
When update_ms is set, pstore_get_records() will be called when there's a new entry. But unlink can be called at the same time and might contend with the open-read-close loop. Depending on the implementation of platform driver, it may be safe or not. But I think it'd be better to protect those race in the first place. Cc: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Kees Cook <keescook@chromium.org>
2016-11-15pstore: Use global ftrace filters for function trace filteringJoel Fernandes1-2/+5
Currently, pstore doesn't have any filters setup for function tracing. This has the associated overhead and may not be useful for users looking for tracing specific set of functions. ftrace's regular function trace filtering is done writing to tracing/set_ftrace_filter however this is not available if not requested. In order to be able to use this feature, the support to request global filtering introduced earlier in the series should be requested before registering the ftrace ops. Here we do the same. Signed-off-by: Joel Fernandes <joelaf@google.com> Signed-off-by: Kees Cook <keescook@chromium.org>
2016-11-15pstore: Clarify context field przs as dprzsKees Cook1-12/+12
Since "przs" (persistent ram zones) is a general name in the code now, so rename the Oops-dump zones to dprzs from przs. Based on a patch from Nobuhiro Iwamatsu. Signed-off-by: Kees Cook <keescook@chromium.org>
2016-11-15pstore: improve error report for failed setupKees Cook1-19/+34
When setting ramoops record sizes, sometimes it's not clear which parameters contributed to the allocation failure. This adds a per-zone name and expands the failure reports. Signed-off-by: Kees Cook <keescook@chromium.org>
2016-11-15pstore: Merge per-CPU ftrace records into oneJoel Fernandes1-13/+109
Up until this patch, each of the per CPU ftrace buffers appear as a separate ftrace-ramoops-N file. In this patch we merge all the zones into one and populate a single ftrace-ramoops-0 file. Signed-off-by: Joel Fernandes <joelaf@google.com> [kees: clarified variables names, added -ENOMEM handling] Signed-off-by: Kees Cook <keescook@chromium.org>
2016-11-15pstore: Add ftrace timestamp counterJoel Fernandes3-37/+9
In preparation for merging the per CPU buffers into one buffer when we retrieve the pstore ftrace data, we store the timestamp as a counter in the ftrace pstore record. We store the CPU number as well if !PSTORE_CPU_IN_IP, in this case we shift the counter and may lose ordering there but we preserve the same record size. The timestamp counter is also racy, and not doing any locking or synchronization here results in the benefit of lower overhead. Since we don't care much here for exact ordering of function traces across CPUs, we don't synchronize and may lose some counter updates but I'm ok with that. Using trace_clock() results in much lower performance so avoid using it since we don't want accuracy in timestamp and need a rough ordering to perform merge. Signed-off-by: Joel Fernandes <joelaf@google.com> [kees: updated commit message, added comments] Signed-off-by: Kees Cook <keescook@chromium.org>
2016-11-15ramoops: Split ftrace buffer space into per-CPU zonesJoel Fernandes1-17/+55
If the RAMOOPS_FLAG_FTRACE_PER_CPU flag is passed to ramoops pdata, split the ftrace space into multiple zones depending on the number of CPUs. This speeds up the performance of function tracing by about 280% in my tests as we avoid the locking. The trade off being lesser space available per CPU. Let the ramoops user decide which option they want based on pdata flag. Signed-off-by: Joel Fernandes <joelaf@google.com> [kees: added max_ftrace_cnt to track size, added DT logic and docs] Signed-off-by: Kees Cook <keescook@chromium.org>
2016-11-15pstore: Make ramoops_init_przs generic for other prz arraysKees Cook1-28/+54
Currently ramoops_init_przs() is hard wired only for panic dump zone array. In preparation for the ftrace zone array (one zone per-cpu) and pmsg zone array, make the function more generic to be able to handle this case. Heavily based on similar work from Joel Fernandes. Signed-off-by: Kees Cook <keescook@chromium.org>
2016-11-15pstore: Allow prz to control need for lockingJoel Fernandes2-11/+18
In preparation of not locking at all for certain buffers depending on if there's contention, make locking optional depending on the initialization of the prz. Signed-off-by: Joel Fernandes <joelaf@google.com> [kees: moved locking flag into prz instead of via caller arguments] Signed-off-by: Kees Cook <keescook@chromium.org>
2016-11-11pstore: Warn on PSTORE_TYPE_PMSG using deprecated functionJoel Fernandes1-4/+2
PMSG now uses ramoops_pstore_write_buf_user() instead of ...write_buf(). Print a ratelimited warning if gets accidentally called. Signed-off-by: Joel Fernandes <joelaf@google.com> [kees: adjusted commit log and added -EINVAL return] Signed-off-by: Kees Cook <keescook@chromium.org>
2016-11-11pstore: Make spinlock per zone instead of globalJoel Fernandes1-6/+5
Currently pstore has a global spinlock for all zones. Since the zones are independent and modify different areas of memory, there's no need to have a global lock, so we should use a per-zone lock as introduced here. Also, when ramoops's ftrace use-case has a FTRACE_PER_CPU flag introduced later, which splits the ftrace memory area into a single zone per CPU, it will eliminate the need for locking. In preparation for this, make the locking optional. Signed-off-by: Joel Fernandes <joelaf@google.com> [kees: updated commit message] Signed-off-by: Kees Cook <keescook@chromium.org>
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