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* x86/MSR: make msr_class a static const structureIvan Orlov2023-08-051-15/+16
| | | | | | | | | | | | | | | | | | Now that the driver core allows for struct class to be in read-only memory, move the msr_class structure to be declared at build time placing it into read-only memory, instead of having to be dynamically allocated at boot time. Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: x86@kernel.org Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ivan Orlov <ivan.orlov0322@gmail.com> Link: https://lore.kernel.org/r/20230620144431.583290-5-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* driver core: class: remove module * from class_create()Greg Kroah-Hartman2023-03-171-1/+1
| | | | | | | | | | | | The module pointer in class_create() never actually did anything, and it shouldn't have been requred to be set as a parameter even if it did something. So just remove it and fix up all callers of the function in the kernel tree at the same time. Cc: "Rafael J. Wysocki" <rafael@kernel.org> Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Link: https://lore.kernel.org/r/20230313181843.1207845-4-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* driver core: make struct class.devnode() take a const *Greg Kroah-Hartman2022-11-241-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The devnode() in struct class should not be modifying the device that is passed into it, so mark it as a const * and propagate the function signature changes out into all relevant subsystems that use this callback. Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Reinette Chatre <reinette.chatre@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: x86@kernel.org Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Cc: Jens Axboe <axboe@kernel.dk> Cc: Justin Sanders <justin@coraid.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Sumit Semwal <sumit.semwal@linaro.org> Cc: Benjamin Gaignard <benjamin.gaignard@collabora.com> Cc: Liam Mark <lmark@codeaurora.org> Cc: Laura Abbott <labbott@redhat.com> Cc: Brian Starkey <Brian.Starkey@arm.com> Cc: John Stultz <jstultz@google.com> Cc: "Christian König" <christian.koenig@amd.com> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Maxime Ripard <mripard@kernel.org> Cc: Thomas Zimmermann <tzimmermann@suse.de> Cc: David Airlie <airlied@gmail.com> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Leon Romanovsky <leon@kernel.org> Cc: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Mauro Carvalho Chehab <mchehab@kernel.org> Cc: Sean Young <sean@mess.org> Cc: Frank Haverkamp <haver@linux.ibm.com> Cc: Jiri Slaby <jirislaby@kernel.org> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Alex Williamson <alex.williamson@redhat.com> Cc: Cornelia Huck <cohuck@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> Cc: Jaroslav Kysela <perex@perex.cz> Cc: Takashi Iwai <tiwai@suse.com> Cc: Hans Verkuil <hverkuil-cisco@xs4all.nl> Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Cc: Xie Yongji <xieyongji@bytedance.com> Cc: Gautam Dawar <gautam.dawar@xilinx.com> Cc: Dan Carpenter <error27@gmail.com> Cc: Eli Cohen <elic@nvidia.com> Cc: Parav Pandit <parav@nvidia.com> Cc: Maxime Coquelin <maxime.coquelin@redhat.com> Cc: alsa-devel@alsa-project.org Cc: dri-devel@lists.freedesktop.org Cc: kvm@vger.kernel.org Cc: linaro-mm-sig@lists.linaro.org Cc: linux-block@vger.kernel.org Cc: linux-input@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-media@vger.kernel.org Cc: linux-rdma@vger.kernel.org Cc: linux-scsi@vger.kernel.org Cc: linux-usb@vger.kernel.org Cc: virtualization@lists.linux-foundation.org Link: https://lore.kernel.org/r/20221123122523.1332370-2-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* x86/MSR: Filter MSR writes through X86_IOC_WRMSR_REGS ioctl tooMisono Tomohiro2021-01-271-0/+7
| | | | | | | | | | | | | | | | | | Commit a7e1f67ed29f ("x86/msr: Filter MSR writes") introduced a module parameter to disable writing to the MSR device file and tainted the kernel upon writing. As MSR registers can be written by the X86_IOC_WRMSR_REGS ioctl too, the same filtering and tainting should be applied to the ioctl as well. [ bp: Massage commit message and space out statements. ] Fixes: a7e1f67ed29f ("x86/msr: Filter MSR writes") Signed-off-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20210127122456.13939-1-misono.tomohiro@jp.fujitsu.com
* x86/msr: Add a pointer to an URL which contains further detailsBorislav Petkov2020-12-081-1/+2
| | | | | | | | | | After having collected the majority of reports about MSRs being written by userspace tools and what tools those are, and all newer reports mostly repeating, add an URL where detailed information is gathered and kept up-to-date. Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20201205002825.19107-1-bp@alien8.de
* x86/msr: Downgrade unrecognized MSR messageBorislav Petkov2020-11-191-2/+2
| | | | | | | It is a warning and not an error so use pr_warn(). Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20201118123806.19672-1-bp@alien8.de
* x86/msr: Do not allow writes to MSR_IA32_ENERGY_PERF_BIASBorislav Petkov2020-11-161-3/+0
| | | | | | | | | Now that all in-kernel-tree users are converted to using the sysfs file, remove the MSR from the "allowlist". Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Shuah Khan <skhan@linuxfoundation.org> Link: https://lkml.kernel.org/r/20201029190259.3476-5-bp@alien8.de
* x86/msr: Make source of unrecognised MSR writes unambiguousChris Down2020-08-221-2/+2
| | | | | | | | | | | | In many cases, task_struct.comm isn't enough to distinguish the offender, since for interpreted languages it's likely just going to be "python3" or whatever. Add the pid to make it unambiguous. [ bp: Make the printk string a single line for easier grepping. ] Signed-off-by: Chris Down <chris@chrisdown.name> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/6f6fbd0ee6c99bc5e47910db700a6642159db01b.1598011595.git.chris@chrisdown.name
* x86/msr: Prevent userspace MSR access from dominating the consoleChris Down2020-08-221-3/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Applications which manipulate MSRs from userspace often do so infrequently, and all at once. As such, the default printk ratelimit architecture supplied by pr_err_ratelimited() doesn't do enough to prevent kmsg becoming completely overwhelmed with their messages and pushing other salient information out of the circular buffer. In one case, I saw over 80% of kmsg being filled with these messages, and the default kmsg buffer being completely filled less than 5 minutes after boot(!). Make things much less aggressive, while still achieving the original goal of fiter_write(). Operators will still get warnings that MSRs are being manipulated from userspace, but they won't have other also potentially useful messages pushed out of the kmsg buffer. Of course, one can boot with `allow_writes=1` to avoid these messages at all, but that then has the downfall that one doesn't get _any_ notification at all about these problems in the first place, and so is much less likely to forget to fix it. One might rather it was less binary: it was still logged, just less often, so that application developers _do_ have the incentive to improve their current methods, without the kernel having to push other useful stuff out of the kmsg buffer. This one example isn't the point, of course: I'm sure there are plenty of other non-ideal-but-pragmatic cases where people are writing to MSRs from userspace right now, and it will take time for those people to find other solutions. Overall, keep the intent of the original patch, while mitigating its sometimes heavy effects on kmsg composition. [ bp: Massage a bit. ] Signed-off-by: Chris Down <chris@chrisdown.name> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/563994ef132ce6cffd28fc659254ca37d032b5ef.1598011595.git.chris@chrisdown.name
* x86/msr: Filter MSR writesBorislav Petkov2020-06-251-0/+69
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add functionality to disable writing to MSRs from userspace. Writes can still be allowed by supplying the allow_writes=on module parameter. The kernel will be tainted so that it shows in oopses. Having unfettered access to all MSRs on a system is and has always been a disaster waiting to happen. Think performance counter MSRs, MSRs with sticky or locked bits, MSRs making major system changes like loading microcode, MTRRs, PAT configuration, TSC counter, security mitigations MSRs, you name it. This also destroys all the kernel's caching of MSR values for performance, as the recent case with MSR_AMD64_LS_CFG showed. Another example is writing MSRs by mistake by simply typing the wrong MSR address. System freezes have been experienced that way. In general, poking at MSRs under the kernel's feet is a bad bad idea. So log writing to MSRs by default. Longer term, such writes will be disabled by default. If userspace still wants to do that, then proper interfaces should be defined which are under the kernel's control and accesses to those MSRs can be synchronized and sanitized properly. [ Fix sparse warnings. ] Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Tested-by: Sean Christopherson <sean.j.christopherson@intel.com> Link: https://lkml.kernel.org/r/20200612105026.GA22660@zn.tnic
* x86/msr: Restrict MSR access when the kernel is locked downMatthew Garrett2019-08-191-0/+8
| | | | | | | | | | | | | Writing to MSRs should not be allowed if the kernel is locked down, since it could lead to execution of arbitrary code in kernel mode. Based on a patch by Kees Cook. Signed-off-by: Matthew Garrett <mjg59@google.com> Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Kees Cook <keescook@chromium.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> cc: x86@kernel.org Signed-off-by: James Morris <jmorris@namei.org>
* treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 142Thomas Gleixner2019-05-301-6/+1
| | | | | | | | | | | | | | | | | | | | | | | | Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation inc 675 mass ave cambridge ma 02139 usa either version 2 of the license or at your option any later version incorporated herein by reference extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 4 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Richard Fontana <rfontana@redhat.com> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190524100844.465381181@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* x86: Clean up 'sizeof x' => 'sizeof(x)'Jordan Borgner2018-10-291-4/+4
| | | | | | | | | | | | | | | | | | "sizeof(x)" is the canonical coding style used in arch/x86 most of the time. Fix the few places that didn't follow the convention. (Also do some whitespace cleanups in a few places while at it.) [ mingo: Rewrote the changelog. ] Signed-off-by: Jordan Borgner <mail@jordan-borgner.de> Cc: Borislav Petkov <bp@alien8.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20181028125828.7rgammkgzep2wpam@JordanDesktop Signed-off-by: Ingo Molnar <mingo@kernel.org>
* x86/msr: Remove bogus cleanup from the error pathThomas Gleixner2016-12-251-1/+0
| | | | | | | | | | The error cleanup which is invoked when the hotplug state setup failed tries to remove the failed state, which is broken. Fixes: 8fba38c937cd ("x86/msr: Convert to hotplug state machine") Reported-by: kernel test robot <fengguang.wu@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Sebastian Siewior <bigeasy@linutronix.de>
* x86/msr: Convert to hotplug state machineSebastian Andrzej Siewior2016-11-221-54/+15
| | | | | | | | | | | | | | | | Install the callbacks via the state machine and let the core invoke the callbacks on the already online CPUs. Move the callbacks to online/offline as there is no point in having the files around before the cpu is online and until its completely gone. [ tglx: Move the callbacks to online/offline ] Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: rt@linuxtronix.de Link: http://lkml.kernel.org/r/20161117183541.8588-4-bigeasy@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* x86/cpufeature: Carve out X86_FEATURE_*Borislav Petkov2016-01-301-1/+1
| | | | | | | | | | | | | | | | | | | | | | Move them to a separate header and have the following dependency: x86/cpufeatures.h <- x86/processor.h <- x86/cpufeature.h This makes it easier to use the header in asm code and not include the whole cpufeature.h and add guards for asm. Suggested-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1453842730-28463-5-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
* new helpers: no_seek_end_llseek{,_size}()Al Viro2015-12-231-23/+1
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* x86, msr: Use seek definitions instead of hard-coded valuesFabian Frederick2014-10-171-2/+2
| | | | | | | | Replace 0/1 by SEEK_SET/SEEK_CUR. Signed-off-by: Fabian Frederick <fabf@skynet.be> Link: http://lkml.kernel.org/r/1413576120-27147-1-git-send-email-fabf@skynet.be Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* x86, msr: Convert printk to pr_foo()Fabian Frederick2014-10-171-2/+3
| | | | | | | | Also define pr_fmt. Signed-off-by: Fabian Frederick <fabf@skynet.be> Link: http://lkml.kernel.org/r/1413576110-27103-1-git-send-email-fabf@skynet.be Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* x86, msr: Use PTR_ERR_OR_ZEROFabian Frederick2014-10-171-1/+1
| | | | | | | | Replace IS_ERR/PTR_ERR Signed-off-by: Fabian Frederick <fabf@skynet.be> Link: http://lkml.kernel.org/r/1413576099-27059-1-git-send-email-fabf@skynet.be Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* x86, msr: Fix CPU hotplug callback registrationSrivatsa S. Bhat2014-03-201-7/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Subsystems that want to register CPU hotplug callbacks, as well as perform initialization for the CPUs that are already online, often do it as shown below: get_online_cpus(); for_each_online_cpu(cpu) init_cpu(cpu); register_cpu_notifier(&foobar_cpu_notifier); put_online_cpus(); This is wrong, since it is prone to ABBA deadlocks involving the cpu_add_remove_lock and the cpu_hotplug.lock (when running concurrently with CPU hotplug operations). Instead, the correct and race-free way of performing the callback registration is: cpu_notifier_register_begin(); for_each_online_cpu(cpu) init_cpu(cpu); /* Note the use of the double underscored version of the API */ __register_cpu_notifier(&foobar_cpu_notifier); cpu_notifier_register_done(); Fix the msr code in x86 by using this latter form of callback registration. Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@kernel.org> Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* x86, msr: Use file_inode(), not f_mapping->hostAndre Richter2013-10-081-1/+1
| | | | | | | | | | | As discussed in [1], exchange f_mapping->host with file_inode(). This is a bug, but happens to be non-manifest in this case. [1] http://lkml.kernel.org/r/20131007190357.GA13318@ZenIV.linux.org.uk Signed-off-by: Andre Richter <andre.o.richter@gmail.com> Link: http://lkml.kernel.org/r/1381224142-3267-1-git-send-email-andre.o.richter@gmail.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* x86: delete __cpuinit usage from all x86 filesPaul Gortmaker2013-07-141-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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. Note that some harmless section mismatch warnings may result, since notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c) are flagged as __cpuinit -- so if we remove the __cpuinit from arch specific callers, we will also get section mismatch warnings. As an intermediate step, we intend to turn the linux/init.h cpuinit content into no-ops as early as possible, since that will get rid of these warnings. In any case, they are temporary and harmless. This removes all the arch/x86 uses of the __cpuinit macros from all C files. x86 only had the one __CPUINIT used in assembly files, and it wasn't paired off with a .previous or a __FINIT, so we can delete it directly w/o any corresponding additional change there. [1] https://lkml.org/lkml/2013/5/20/589 Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: x86@kernel.org Acked-by: Ingo Molnar <mingo@kernel.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
* more file_inode() open-coded instancesAl Viro2013-02-271-5/+4
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* x86/msr: Add capabilities checkAlan Cox2013-01-241-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | At the moment the MSR driver only relies upon file system checks. This means that anything as root with any capability set can write to MSRs. Historically that wasn't very interesting but on modern processors the MSRs are such that writing to them provides several ways to execute arbitary code in kernel space. Sample code and documentation on doing this is circulating and MSR attacks are used on Windows 64bit rootkits already. In the Linux case you still need to be able to open the device file so the impact is fairly limited and reduces the security of some capability and security model based systems down towards that of a generic "root owns the box" setup. Therefore they should require CAP_SYS_RAWIO to prevent an elevation of capabilities. The impact of this is fairly minimal on most setups because they don't have heavy use of capabilities. Those using SELinux, SMACK or AppArmor rules might want to consider if their rulesets on the MSR driver could be tighter. Signed-off-by: Alan Cox <alan@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Horses <stable@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org>
* Use get_online_cpus to avoid races involving CPU hotplugSilas Boyd-Wickizer2012-09-231-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If arch/x86/kernel/msr.c is a module, a CPU might offline or online between the for_each_online_cpu(i) loop and the call to register_hotcpu_notifier in msr_init or the call to unregister_hotcpu_notifier in msr_exit. The potential races can lead to leaks/duplicates, attempts to destroy non-existant devices, or random pointer dereferences. For example, in msr_init if: for_each_online_cpu(i) { err = msr_device_create(i); if (err != 0) goto out_class; } <----- CPU offlines register_hotcpu_notifier(&msr_class_cpu_notifier); and the CPU never onlines before msr_exit, then the module will never call msr_device_destroy for the associated CPU. This fix surrounds for_each_online_cpu and register_hotcpu_notifier or unregister_hotcpu_notifier with get_online_cpus+put_online_cpus. Tested on a VM. Signed-off-by: Silas Boyd-Wickizer <sbw@mit.edu> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* Disintegrate asm/system.h for X86David Howells2012-03-281-1/+0
| | | | | | | | Disintegrate asm/system.h for X86. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: H. Peter Anvin <hpa@zytor.com> cc: x86@kernel.org
* switch device_get_devnode() and ->devnode() to umode_t *Al Viro2012-01-031-1/+1
| | | | | | | both callers of device_get_devnode() are only interested in lower 16bits and nobody tries to return anything wider than 16bit anyway. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* BKL: remove extraneous #include <smp_lock.h>Arnd Bergmann2010-11-171-1/+0
| | | | | | | | | | The big kernel lock has been removed from all these files at some point, leaving only the #include. Remove this too as a cleanup. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* x86: convert cpu notifier to return encapsulate errno valueAkinobu Mita2010-05-271-1/+1
| | | | | | | | | | | | | By the previous modification, the cpu notifier can return encapsulate errno value. This converts the cpu notifiers for msr, cpuid, and therm_throt. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo2010-03-301-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
* x86, msr/cpuid: Pass the number of minors when unregistering MSR and CPUID ↵Russ Anderson2010-01-261-1/+1
| | | | | | | | | | | | drivers. Pass the number of minors when unregistering MSR and CPUID drivers. Reported-by: Dean Nelson <dnelson@redhat.com> Signed-off-by: Dean Nelson <dnelson@redhat.com> LKML-Reference: <20100127023722.GA22305@sgi.com> Signed-off-by: Russ Anderson <rja@sgi.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* x86, msr/cpuid: Register enough minors for the MSR and CPUID driversH. Peter Anvin2009-12-151-2/+2
| | | | | | | | | | | | | | | | | | register_chrdev() hardcodes registering 256 minors, presumably to avoid breaking old drivers. However, we need to register enough minors so that we have all possible CPUs. checkpatch warns on this patch, but the patch is correct: NR_CPUS here is a static *upper bound* on the *maximum CPU index* (not *number of CPUs!*) and that is what we want. Reported-and-tested-by: Russ Anderson <rja@sgi.com> Cc: Tejun Heo <tj@kernel.org> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Takashi Iwai <tiwai@suse.de> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com> LKML-Reference: <tip-*@git.kernel.org>
* x86, msr: Remove incorrect, duplicated code in the MSR driverH. Peter Anvin2009-12-141-3/+2
| | | | | | | | | | | | The MSR driver would compute the values for cpu and c at declaration, and then again in the body of the function. This isn't merely redundant, but unsafe, since cpu might not refer to a valid CPU at that point. Remove the unnecessary and dangerous references in the declarations. This code now matches the equivalent code in the CPUID driver. Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* Merge branch 'x86-cpu-for-linus' of ↵Linus Torvalds2009-12-051-10/+6
|\ | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, msr, cpumask: Use struct cpumask rather than the deprecated cpumask_t x86, cpuid: Simplify the code in cpuid_open x86, cpuid: Remove the bkl from cpuid_open() x86, msr: Remove the bkl from msr_open() x86: AMD Geode LX optimizations x86, msr: Unify rdmsr_on_cpus/wrmsr_on_cpus
| * x86, msr: Remove the bkl from msr_open()Frederic Weisbecker2009-10-071-10/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Remove the big kernel lock from msr_open() as it doesn't protect anything there. The only racy event that can happen here is a concurrent cpu shutdown. So let's look at what could be racy during/after the above event: - The cpu_online() check is racy, but the bkl doesn't help about that anyway it disables preemption but we may be chcking another cpu than the current one. Also the cpu can still become offlined between open and read calls. - The cpu_data(cpu) returns a safe pointer too. It won't be released on cpu offlining. But some fields can be changed from arch/x86/kernel/smpboot.c:remove_siblinginfo() : - phys_proc_id - cpu_core_id Those are not read from msr_open(). What we are checking is the x86_capability that is left untouched on offlining. So this removal looks safe. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: John Kacur <jkacur@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Sven-Thorsten Dietrich <sdietrich@suse.de> LKML-Reference: <1254944602-7382-1-git-send-email-fweisbec@gmail.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* | Driver-Core: extend devnode callbacks to provide permissionsKay Sievers2009-09-191-2/+2
|/ | | | | | | | | | | | | This allows subsytems to provide devtmpfs with non-default permissions for the device node. Instead of the default mode of 0600, null, zero, random, urandom, full, tty, ptmx now have a mode of 0666, which allows non-privileged processes to access standard device nodes in case no other userspace process applies the expected permissions. This also fixes a wrong assignment in pktcdvd and a checkpatch.pl complain. Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* x86, msr: Export the register-setting MSR functions via /dev/*/msrH. Peter Anvin2009-08-311-0/+51
| | | | | | | | | Make it possible to access the all-register-setting/getting MSR functions via the MSR driver. This is implemented as an ioctl() on the standard MSR device node. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Cc: Borislav Petkov <petkovbb@gmail.com>
* x86, msr: Have the _safe MSR functions return -EIO, not -EFAULTH. Peter Anvin2009-08-311-8/+2
| | | | | | | | | | | | | For some reason, the _safe MSR functions returned -EFAULT, not -EIO. However, the only user which cares about the return code as anything other than a boolean is the MSR driver, which wants -EIO. Change it to -EIO across the board. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Cc: Jeremy Fitzhardinge <jeremy@xensource.com> Cc: Chris Wright <chrisw@sous-sol.org> Cc: Alok Kataria <akataria@vmware.com> Cc: Rusty Russell <rusty@rustcorp.com.au>
* Driver Core: x86: add nodename for cpuid and msr drivers.Kay Sievers2009-06-151-0/+6
| | | | | | | | | This adds support to the x86 cpuid and msr drivers to report the proper device name to userspace for their devices. Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jan Blunck <jblunck@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* x86: msr.c fix style problemsJaswinder Singh Rajput2009-01-121-1/+1
| | | | | | | | | | | | | Impact: cleanup Fix: WARNING: Use #include <linux/uaccess.h> instead of <asm/uaccess.h> total: 0 errors, 1 warnings Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86: cleanup some remaining usages of NR_CPUS where s/b nr_cpu_idsMike Travis2009-01-031-1/+1
| | | | | | | | | | | | | | | | | | | | Impact: Reduce future system panics due to cpumask operations using NR_CPUS Insure that code does not look at bits >= nr_cpu_ids as when cpumasks are allocated based on nr_cpu_ids, these extra bits will not be defined. Also some other minor updates: * change in to use cpu accessor function set_cpu_present() instead of directly accessing cpu_present_map w/cpu_clear() [arch/x86/kernel/reboot.c] * use cpumask_of() instead of &cpumask_of_cpu() [arch/x86/kernel/reboot.c] * optimize some cpu_mask_to_apicid_and functions. Signed-off-by: Mike Travis <travis@sgi.com> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* device create: misc: convert device_create_drvdata to device_createGreg Kroah-Hartman2008-10-161-2/+2
| | | | | | | | Now that device_create() has been audited, rename things back to the original call to be sane. Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* x86: msr: correct return value on partial operationsH. Peter Anvin2008-08-251-10/+18
| | | | | | | | Return the correct return value when the MSR driver partially completes a request (we should return the number of bytes actually read or written, instead of the error code.) Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* x86: msr: propagate errors from smp_call_function_single()H. Peter Anvin2008-08-251-4/+10
| | | | | | | | Propagate error (-ENXIO) from smp_call_function_single(). These errors can happen when a CPU is unplugged while the MSR driver is open. Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* x86, msr: fix NULL pointer deref due to msr_open on nonexistent CPUsDarrick J. Wong2008-08-151-1/+1
| | | | | | | | | | | | | | | | msr_open tests for someone trying to open a device for a nonexistent CPU. However, the function always returns 0, not ret like it should, hence userspace can BUG the kernel trivially. This bug was introduced by the cdev lock_kernel pushdown patch last May. The BUG can be reproduced with these commands: # mknod fubar c 202 8 <-- pick a number less than NR_CPUS that is not the number of an online CPU # cat fubar Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* device create: x86: convert device_create to device_create_drvdataGreg Kroah-Hartman2008-07-211-2/+2
| | | | | | | | | | | device_create() is race-prone, so use the race-free device_create_drvdata() instead as device_create() is going away. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* x86: cdev lock_kernel() pushdownJonathan Corbet2008-05-181-4/+12
| | | | | | Push the cdev lock_kernel() call down into the x86 msr and cpuid drivers. Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* PM: Remove destroy_suspended_device()Rafael J. Wysocki2008-04-191-3/+1
| | | | | | | | | | | | | | | | | | After 2.6.24 there was a plan to make the PM core acquire all device semaphores during a suspend/hibernation to protect itself from concurrent operations involving device objects. That proved to be too heavy-handed and we found a better way to achieve the goal, but before it happened, we had introduced the functions device_pm_schedule_removal() and destroy_suspended_device() to allow drivers to "safely" destroy a suspended device and we had adapted some drivers to use them. Now that these functions are no longer necessary, it seems reasonable to remove them and modify their users to use the normal device unregistration instead. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* x86: coding style fixes to arch/x86/kernel/msr.cPaolo Ciarrocchi2008-04-171-2/+2
| | | | | | | | | | | | | | | | | | | | | | Before: total: 2 errors, 0 warnings, 231 lines checked After: total: 0 errors, 0 warnings, 231 lines checked No code changed: arch/x86/kernel/msr.o: text data bss dec hex filename 1199 12 4 1215 4bf msr.o.before 1199 12 4 1215 4bf msr.o.after md5: 604be0d07d829bc52a9346babd084bdc msr.o.before.asm 604be0d07d829bc52a9346babd084bdc msr.o.after.asm Signed-off-by: Paolo Ciarrocchi <paolo.ciarrocchi@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
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