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2022-03-11Documentation/hw-vuln: Update spectre docPeter Zijlstra
commit 5ad3eb1132453b9795ce5fd4572b1c18b292cca9 upstream. Update the doc with the new fun. [ bp: Massage commit message. ] Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> [fllinden@amazon.com: backported to 5.4] Signed-off-by: Frank van der Linden <fllinden@amazon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-05Input: i8042 - add deferred probe supportTakashi Iwai
[ Upstream commit 9222ba68c3f4065f6364b99cc641b6b019ef2d42 ] We've got a bug report about the non-working keyboard on ASUS ZenBook UX425UA. It seems that the PS/2 device isn't ready immediately at boot but takes some seconds to get ready. Until now, the only workaround is to defer the probe, but it's available only when the driver is a module. However, many distros, including openSUSE as in the original report, build the PS/2 input drivers into kernel, hence it won't work easily. This patch adds the support for the deferred probe for i8042 stuff as a workaround of the problem above. When the deferred probe mode is enabled and the device couldn't be probed, it'll be repeated with the standard deferred probe mechanism. The deferred probe mode is enabled either via the new option i8042.probe_defer or via the quirk table entry. As of this patch, the quirk table contains only ASUS ZenBook UX425UA. The deferred probe part is based on Fabio's initial work. BugLink: https://bugzilla.suse.com/show_bug.cgi?id=1190256 Signed-off-by: Takashi Iwai <tiwai@suse.de> Tested-by: Samuel Čavoj <samuel@cavoj.net> Link: https://lore.kernel.org/r/20211117063757.11380-1-tiwai@suse.de Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-12-29KVM: VMX: Fix stale docs for kvm-intel.emulate_invalid_guest_stateSean Christopherson
commit 0ff29701ffad9a5d5a24344d8b09f3af7b96ffda upstream. Update the documentation for kvm-intel's emulate_invalid_guest_state to rectify the description of KVM's default behavior, and to document that the behavior and thus parameter only applies to L1. Fixes: a27685c33acc ("KVM: VMX: Emulate invalid guest state by default") Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20211207193006.120997-4-seanjc@google.com> Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-17xen/balloon: add late_initcall_sync() for initial ballooning doneJuergen Gross
commit 40fdea0284bb20814399da0484a658a96c735d90 upstream. When running as PVH or HVM guest with actual memory < max memory the hypervisor is using "populate on demand" in order to allow the guest to balloon down from its maximum memory size. For this to work correctly the guest must not touch more memory pages than its target memory size as otherwise the PoD cache will be exhausted and the guest is crashed as a result of that. In extreme cases ballooning down might not be finished today before the init process is started, which can consume lots of memory. In order to avoid random boot crashes in such cases, add a late init call to wait for ballooning down having finished for PVH/HVM guests. Warn on console if initial ballooning fails, panic() after stalling for more than 3 minutes per default. Add a module parameter for changing this timeout. [boris: replaced pr_info() with pr_notice()] Cc: <stable@vger.kernel.org> Reported-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com> Signed-off-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/20211102091944.17487-1-jgross@suse.com Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-14clocksource: Retry clock read if long delays detectedPaul E. McKenney
[ Upstream commit db3a34e17433de2390eb80d436970edcebd0ca3e ] When the clocksource watchdog marks a clock as unstable, this might be due to that clock being unstable or it might be due to delays that happen to occur between the reads of the two clocks. Yes, interrupts are disabled across those two reads, but there are no shortage of things that can delay interrupts-disabled regions of code ranging from SMI handlers to vCPU preemption. It would be good to have some indication as to why the clock was marked unstable. Therefore, re-read the watchdog clock on either side of the read from the clock under test. If the watchdog clock shows an excessive time delta between its pair of reads, the reads are retried. The maximum number of retries is specified by a new kernel boot parameter clocksource.max_cswd_read_retries, which defaults to three, that is, up to four reads, one initial and up to three retries. If more than one retry was required, a message is printed on the console (the occasional single retry is expected behavior, especially in guest OSes). If the maximum number of retries is exceeded, the clock under test will be marked unstable. However, the probability of this happening due to various sorts of delays is quite small. In addition, the reason (clock-read delays) for the unstable marking will be apparent. Reported-by: Chris Mason <clm@fb.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Feng Tang <feng.tang@intel.com> Link: https://lore.kernel.org/r/20210527190124.440372-1-paulmck@kernel.org Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-01-27x86/xen: Add xen_no_vector_callback option to test PCI INTX deliveryDavid Woodhouse
[ Upstream commit b36b0fe96af13460278bf9b173beced1bd15f85d ] It's useful to be able to test non-vector event channel delivery, to make sure Linux will work properly on older Xen which doesn't have it. It's also useful for those working on Xen and Xen-compatible hypervisors, because there are guest kernels still in active use which use PCI INTX even when vector delivery is available. Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lore.kernel.org/r/20210106153958.584169-4-dwmw2@infradead.org Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-12-21USB: UAS: introduce a quirk to set no_write_sameOliver Neukum
commit 8010622c86ca5bb44bc98492f5968726fc7c7a21 upstream. UAS does not share the pessimistic assumption storage is making that devices cannot deal with WRITE_SAME. A few devices supported by UAS, are reported to not deal well with WRITE_SAME. Those need a quirk. Add it to the device that needs it. Reported-by: David C. Partridge <david.partridge@perdrix.co.uk> Signed-off-by: Oliver Neukum <oneukum@suse.com> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20201209152639.9195-1-oneukum@suse.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-22powerpc/64s: flush L1D after user accessesNicholas Piggin
commit 9a32a7e78bd0cd9a9b6332cbdc345ee5ffd0c5de upstream. IBM Power9 processors can speculatively operate on data in the L1 cache before it has been completely validated, via a way-prediction mechanism. It is not possible for an attacker to determine the contents of impermissible memory using this method, since these systems implement a combination of hardware and software security measures to prevent scenarios where protected data could be leaked. However these measures don't address the scenario where an attacker induces the operating system to speculatively execute instructions using data that the attacker controls. This can be used for example to speculatively bypass "kernel user access prevention" techniques, as discovered by Anthony Steinhauser of Google's Safeside Project. This is not an attack by itself, but there is a possibility it could be used in conjunction with side-channels or other weaknesses in the privileged code to construct an attack. This issue can be mitigated by flushing the L1 cache between privilege boundaries of concern. This patch flushes the L1 cache after user accesses. This is part of the fix for CVE-2020-4788. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-22powerpc/64s: flush L1D on kernel entryNicholas Piggin
commit f79643787e0a0762d2409b7b8334e83f22d85695 upstream. [backporting note: we need to mark some exception handlers as out-of-line because the flushing makes them take too much space -- dja] IBM Power9 processors can speculatively operate on data in the L1 cache before it has been completely validated, via a way-prediction mechanism. It is not possible for an attacker to determine the contents of impermissible memory using this method, since these systems implement a combination of hardware and software security measures to prevent scenarios where protected data could be leaked. However these measures don't address the scenario where an attacker induces the operating system to speculatively execute instructions using data that the attacker controls. This can be used for example to speculatively bypass "kernel user access prevention" techniques, as discovered by Anthony Steinhauser of Google's Safeside Project. This is not an attack by itself, but there is a possibility it could be used in conjunction with side-channels or other weaknesses in the privileged code to construct an attack. This issue can be mitigated by flushing the L1 cache between privilege boundaries of concern. This patch flushes the L1 cache on kernel entry. This is part of the fix for CVE-2020-4788. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-05xen/events: defer eoi in case of excessive number of eventsJuergen Gross
commit e99502f76271d6bc4e374fe368c50c67a1fd3070 upstream. In case rogue guests are sending events at high frequency it might happen that xen_evtchn_do_upcall() won't stop processing events in dom0. As this is done in irq handling a crash might be the result. In order to avoid that, delay further inter-domain events after some time in xen_evtchn_do_upcall() by forcing eoi processing into a worker on the same cpu, thus inhibiting new events coming in. The time after which eoi processing is to be delayed is configurable via a new module parameter "event_loop_timeout" which specifies the maximum event loop time in jiffies (default: 2, the value was chosen after some tests showing that a value of 2 was the lowest with an only slight drop of dom0 network throughput while multiple guests performed an event storm). How long eoi processing will be delayed can be specified via another parameter "event_eoi_delay" (again in jiffies, default 10, again the value was chosen after testing with different delay values). This is part of XSA-332. Cc: stable@vger.kernel.org Reported-by: Julien Grall <julien@xen.org> Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Reviewed-by: Wei Liu <wl@xen.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-29x86/fpu: Allow multiple bits in clearcpuid= parameterArvind Sankar
[ Upstream commit 0a4bb5e5507a585532cc413125b921c8546fc39f ] Commit 0c2a3913d6f5 ("x86/fpu: Parse clearcpuid= as early XSAVE argument") changed clearcpuid parsing from __setup() to cmdline_find_option(). While the __setup() function would have been called for each clearcpuid= parameter on the command line, cmdline_find_option() will only return the last one, so the change effectively made it impossible to disable more than one bit. Allow a comma-separated list of bit numbers as the argument for clearcpuid to allow multiple bits to be disabled again. Log the bits being disabled for informational purposes. Also fix the check on the return value of cmdline_find_option(). It returns -1 when the option is not found, so testing as a boolean is incorrect. Fixes: 0c2a3913d6f5 ("x86/fpu: Parse clearcpuid= as early XSAVE argument") Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20200907213919.2423441-1-nivedita@alum.mit.edu Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-10x86/speculation: Add Special Register Buffer Data Sampling (SRBDS) mitigationMark Gross
commit 7e5b3c267d256822407a22fdce6afdf9cd13f9fb upstream SRBDS is an MDS-like speculative side channel that can leak bits from the random number generator (RNG) across cores and threads. New microcode serializes the processor access during the execution of RDRAND and RDSEED. This ensures that the shared buffer is overwritten before it is released for reuse. While it is present on all affected CPU models, the microcode mitigation is not needed on models that enumerate ARCH_CAPABILITIES[MDS_NO] in the cases where TSX is not supported or has been disabled with TSX_CTRL. The mitigation is activated by default on affected processors and it increases latency for RDRAND and RDSEED instructions. Among other effects this will reduce throughput from /dev/urandom. * Enable administrator to configure the mitigation off when desired using either mitigations=off or srbds=off. * Export vulnerability status via sysfs * Rename file-scoped macros to apply for non-whitelist table initializations. [ bp: Massage, - s/VULNBL_INTEL_STEPPING/VULNBL_INTEL_STEPPINGS/g, - do not read arch cap MSR a second time in tsx_fused_off() - just pass it in, - flip check in cpu_set_bug_bits() to save an indentation level, - reflow comments. jpoimboe: s/Mitigated/Mitigation/ in user-visible strings tglx: Dropped the fused off magic for now ] Signed-off-by: Mark Gross <mgross@linux.intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Tested-by: Neelima Krishnan <neelima.krishnan@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-29USB: hub: Revert commit bd0e6c9614b9 ("usb: hub: try old enumeration scheme ↵Alan Stern
first for high speed devices") commit 3155f4f40811c5d7e3c686215051acf504e05565 upstream. Commit bd0e6c9614b9 ("usb: hub: try old enumeration scheme first for high speed devices") changed the way the hub driver enumerates high-speed devices. Instead of using the "new" enumeration scheme first and switching to the "old" scheme if that doesn't work, we start with the "old" scheme. In theory this is better because the "old" scheme is slightly faster -- it involves resetting the device only once instead of twice. However, for a long time Windows used only the "new" scheme. Zeng Tao said that Windows 8 and later use the "old" scheme for high-speed devices, but apparently there are some devices that don't like it. William Bader reports that the Ricoh webcam built into his Sony Vaio laptop not only doesn't enumerate under the "old" scheme, it gets hung up so badly that it won't then enumerate under the "new" scheme! Only a cold reset will fix it. Therefore we will revert the commit and go back to trying the "new" scheme first for high-speed devices. Reported-and-tested-by: William Bader <williambader@hotmail.com> Ref: https://bugzilla.kernel.org/show_bug.cgi?id=207219 Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Fixes: bd0e6c9614b9 ("usb: hub: try old enumeration scheme first for high speed devices") CC: Zeng Tao <prime.zeng@hisilicon.com> CC: <stable@vger.kernel.org> Link: https://lore.kernel.org/r/Pine.LNX.4.44L0.2004221611230.11262-100000@iolanthe.rowland.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-23docs: Fix path to MTD command line partition parserJonathan Neuschäfer
commit fb2511247dc4061fd122d0195838278a4a0b7b59 upstream. cmdlinepart.c has been moved to drivers/mtd/parsers/. Fixes: a3f12a35c91d ("mtd: parsers: Move CMDLINE parser") Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-21ACPI: watchdog: Allow disabling WDAT at bootJean Delvare
[ Upstream commit 3f9e12e0df012c4a9a7fd7eb0d3ae69b459d6b2c ] In case the WDAT interface is broken, give the user an option to ignore it to let a native driver bind to the watchdog device instead. Signed-off-by: Jean Delvare <jdelvare@suse.de> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-09ACPI: sysfs: Change ACPI_MASKABLE_GPE_MAX to 0x100Yunfeng Ye
commit a7583e72a5f22470d3e6fd3b6ba912892242339f upstream. The commit 0f27cff8597d ("ACPI: sysfs: Make ACPI GPE mask kernel parameter cover all GPEs") says: "Use a bitmap of size 0xFF instead of a u64 for the GPE mask so 256 GPEs can be masked" But the masking of GPE 0xFF it not supported and the check condition "gpe > ACPI_MASKABLE_GPE_MAX" is not valid because the type of gpe is u8. So modify the macro ACPI_MASKABLE_GPE_MAX to 0x100, and drop the "gpe > ACPI_MASKABLE_GPE_MAX" check. In addition, update the docs "Format" for acpi_mask_gpe parameter. Fixes: 0f27cff8597d ("ACPI: sysfs: Make ACPI GPE mask kernel parameter cover all GPEs") Signed-off-by: Yunfeng Ye <yeyunfeng@huawei.com> [ rjw: Use u16 as gpe data type in acpi_gpe_apply_masked_gpes() ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-12-17USB: documentation: flags on usb-storage versus UASOliver Neukum
commit 65cc8bf99349f651a0a2cee69333525fe581f306 upstream. Document which flags work storage, UAS or both Signed-off-by: Oliver Neukum <oneukum@suse.com> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20191114112758.32747-4-oneukum@suse.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-29x86/speculation: Fix incorrect MDS/TAA mitigation statusWaiman Long
commit 64870ed1b12e235cfca3f6c6da75b542c973ff78 upstream. For MDS vulnerable processors with TSX support, enabling either MDS or TAA mitigations will enable the use of VERW to flush internal processor buffers at the right code path. IOW, they are either both mitigated or both not. However, if the command line options are inconsistent, the vulnerabilites sysfs files may not report the mitigation status correctly. For example, with only the "mds=off" option: vulnerabilities/mds:Vulnerable; SMT vulnerable vulnerabilities/tsx_async_abort:Mitigation: Clear CPU buffers; SMT vulnerable The mds vulnerabilities file has wrong status in this case. Similarly, the taa vulnerability file will be wrong with mds mitigation on, but taa off. Change taa_select_mitigation() to sync up the two mitigation status and have them turned off if both "mds=off" and "tsx_async_abort=off" are present. Update documentation to emphasize the fact that both "mds=off" and "tsx_async_abort=off" have to be specified together for processors that are affected by both TAA and MDS to be effective. [ bp: Massage and add kernel-parameters.txt change too. ] Fixes: 1b42f017415b ("x86/speculation/taa: Add mitigation for TSX Async Abort") Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: linux-doc@vger.kernel.org Cc: Mark Gross <mgross@linux.intel.com> Cc: <stable@vger.kernel.org> Cc: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Tyler Hicks <tyhicks@canonical.com> Cc: x86-ml <x86@kernel.org> Link: https://lkml.kernel.org/r/20191115161445.30809-2-longman@redhat.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-04kvm: x86: mmu: Recovery of shattered NX large pagesJunaid Shahid
The page table pages corresponding to broken down large pages are zapped in FIFO order, so that the large page can potentially be recovered, if it is not longer being used for execution. This removes the performance penalty for walking deeper EPT page tables. By default, one large page will last about one hour once the guest reaches a steady state. Signed-off-by: Junaid Shahid <junaids@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2019-11-04kvm: mmu: ITLB_MULTIHIT mitigationPaolo Bonzini
With some Intel processors, putting the same virtual address in the TLB as both a 4 KiB and 2 MiB page can confuse the instruction fetch unit and cause the processor to issue a machine check resulting in a CPU lockup. Unfortunately when EPT page tables use huge pages, it is possible for a malicious guest to cause this situation. Add a knob to mark huge pages as non-executable. When the nx_huge_pages parameter is enabled (and we are using EPT), all huge pages are marked as NX. If the guest attempts to execute in one of those pages, the page is broken down into 4K pages, which are then marked executable. This is not an issue for shadow paging (except nested EPT), because then the host is in control of TLB flushes and the problematic situation cannot happen. With nested EPT, again the nested guest can cause problems shadow and direct EPT is treated in the same way. [ tglx: Fixup default to auto and massage wording a bit ] Originally-by: Junaid Shahid <junaids@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2019-10-28x86/speculation/taa: Add documentation for TSX Async AbortPawan Gupta
Add the documenation for TSX Async Abort. Include the description of the issue, how to check the mitigation state, control the mitigation, guidance for system administrators. [ bp: Add proper SPDX tags, touch ups by Josh and me. ] Co-developed-by: Antonio Gomez Iglesias <antonio.gomez.iglesias@intel.com> Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Antonio Gomez Iglesias <antonio.gomez.iglesias@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Mark Gross <mgross@linux.intel.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
2019-10-28x86/tsx: Add "auto" option to the tsx= cmdline parameterPawan Gupta
Platforms which are not affected by X86_BUG_TAA may want the TSX feature enabled. Add "auto" option to the TSX cmdline parameter. When tsx=auto disable TSX when X86_BUG_TAA is present, otherwise enable TSX. More details on X86_BUG_TAA can be found here: https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/tsx_async_abort.html [ bp: Extend the arg buffer to accommodate "auto\0". ] Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
2019-10-28x86/cpu: Add a "tsx=" cmdline option with TSX disabled by defaultPawan Gupta
Add a kernel cmdline parameter "tsx" to control the Transactional Synchronization Extensions (TSX) feature. On CPUs that support TSX control, use "tsx=on|off" to enable or disable TSX. Not specifying this option is equivalent to "tsx=off". This is because on certain processors TSX may be used as a part of a speculative side channel attack. Carve out the TSX controlling functionality into a separate compilation unit because TSX is a CPU feature while the TSX async abort control machinery will go to cpu/bugs.c. [ bp: - Massage, shorten and clear the arg buffer. - Clarifications of the tsx= possible options - Josh. - Expand on TSX_CTRL availability - Pawan. ] Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
2019-10-12Merge tag 'for-linus-5.4-rc3-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen fixes from Juergen Gross: - correct panic handling when running as a Xen guest - cleanup the Xen grant driver to remove printing a pointer being always NULL - remove a soon to be wrong call of of_dma_configure() * tag 'for-linus-5.4-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen: Stop abusing DT of_dma_configure API xen/grant-table: remove unnecessary printing x86/xen: Return from panic notifier
2019-10-07x86/xen: Return from panic notifierBoris Ostrovsky
Currently execution of panic() continues until Xen's panic notifier (xen_panic_event()) is called at which point we make a hypercall that never returns. This means that any notifier that is supposed to be called later as well as significant part of panic() code (such as pstore writes from kmsg_dump()) is never executed. There is no reason for xen_panic_event() to be this last point in execution since panic()'s emergency_restart() will call into xen_emergency_restart() from where we can perform our hypercall. Nevertheless, we will provide xen_legacy_crash boot option that will preserve original behavior during crash. This option could be used, for example, if running kernel dumper (which happens after panic notifiers) is undesirable. Reported-by: James Dingwall <james@dingwall.me.uk> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: Juergen Gross <jgross@suse.com>
2019-09-28Merge branch 'next-lockdown' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull kernel lockdown mode from James Morris: "This is the latest iteration of the kernel lockdown patchset, from Matthew Garrett, David Howells and others. From the original description: This patchset introduces an optional kernel lockdown feature, intended to strengthen the boundary between UID 0 and the kernel. When enabled, various pieces of kernel functionality are restricted. Applications that rely on low-level access to either hardware or the kernel may cease working as a result - therefore this should not be enabled without appropriate evaluation beforehand. The majority of mainstream distributions have been carrying variants of this patchset for many years now, so there's value in providing a doesn't meet every distribution requirement, but gets us much closer to not requiring external patches. There are two major changes since this was last proposed for mainline: - Separating lockdown from EFI secure boot. Background discussion is covered here: https://lwn.net/Articles/751061/ - Implementation as an LSM, with a default stackable lockdown LSM module. This allows the lockdown feature to be policy-driven, rather than encoding an implicit policy within the mechanism. The new locked_down LSM hook is provided to allow LSMs to make a policy decision around whether kernel functionality that would allow tampering with or examining the runtime state of the kernel should be permitted. The included lockdown LSM provides an implementation with a simple policy intended for general purpose use. This policy provides a coarse level of granularity, controllable via the kernel command line: lockdown={integrity|confidentiality} Enable the kernel lockdown feature. If set to integrity, kernel features that allow userland to modify the running kernel are disabled. If set to confidentiality, kernel features that allow userland to extract confidential information from the kernel are also disabled. This may also be controlled via /sys/kernel/security/lockdown and overriden by kernel configuration. New or existing LSMs may implement finer-grained controls of the lockdown features. Refer to the lockdown_reason documentation in include/linux/security.h for details. The lockdown feature has had signficant design feedback and review across many subsystems. This code has been in linux-next for some weeks, with a few fixes applied along the way. Stephen Rothwell noted that commit 9d1f8be5cf42 ("bpf: Restrict bpf when kernel lockdown is in confidentiality mode") is missing a Signed-off-by from its author. Matthew responded that he is providing this under category (c) of the DCO" * 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (31 commits) kexec: Fix file verification on S390 security: constify some arrays in lockdown LSM lockdown: Print current->comm in restriction messages efi: Restrict efivar_ssdt_load when the kernel is locked down tracefs: Restrict tracefs when the kernel is locked down debugfs: Restrict debugfs when the kernel is locked down kexec: Allow kexec_file() with appropriate IMA policy when locked down lockdown: Lock down perf when in confidentiality mode bpf: Restrict bpf when kernel lockdown is in confidentiality mode lockdown: Lock down tracing and perf kprobes when in confidentiality mode lockdown: Lock down /proc/kcore x86/mmiotrace: Lock down the testmmiotrace module lockdown: Lock down module params that specify hardware parameters (eg. ioport) lockdown: Lock down TIOCSSERIAL lockdown: Prohibit PCMCIA CIS storage when the kernel is locked down acpi: Disable ACPI table override if the kernel is locked down acpi: Ignore acpi_rsdp kernel param when the kernel has been locked down ACPI: Limit access to custom_method when the kernel is locked down x86/msr: Restrict MSR access when the kernel is locked down x86: Lock down IO port access when the kernel is locked down ...
2019-09-24Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge updates from Andrew Morton: - a few hot fixes - ocfs2 updates - almost all of -mm (slab-generic, slab, slub, kmemleak, kasan, cleanups, debug, pagecache, memcg, gup, pagemap, memory-hotplug, sparsemem, vmalloc, initialization, z3fold, compaction, mempolicy, oom-kill, hugetlb, migration, thp, mmap, madvise, shmem, zswap, zsmalloc) * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (132 commits) mm/zsmalloc.c: fix a -Wunused-function warning zswap: do not map same object twice zswap: use movable memory if zpool support allocate movable memory zpool: add malloc_support_movable to zpool_driver shmem: fix obsolete comment in shmem_getpage_gfp() mm/madvise: reduce code duplication in error handling paths mm: mmap: increase sockets maximum memory size pgoff for 32bits mm/mmap.c: refine find_vma_prev() with rb_last() riscv: make mmap allocation top-down by default mips: use generic mmap top-down layout and brk randomization mips: replace arch specific way to determine 32bit task with generic version mips: adjust brk randomization offset to fit generic version mips: use STACK_TOP when computing mmap base address mips: properly account for stack randomization and stack guard gap arm: use generic mmap top-down layout and brk randomization arm: use STACK_TOP when computing mmap base address arm: properly account for stack randomization and stack guard gap arm64, mm: make randomization selected by generic topdown mmap layout arm64, mm: move generic mmap layout functions to mm arm64: consider stack randomization for mmap base only when necessary ...
2019-09-24mm, page_owner, debug_pagealloc: save and dump freeing stack traceVlastimil Babka
The debug_pagealloc functionality is useful to catch buggy page allocator users that cause e.g. use after free or double free. When page inconsistency is detected, debugging is often simpler by knowing the call stack of process that last allocated and freed the page. When page_owner is also enabled, we record the allocation stack trace, but not freeing. This patch therefore adds recording of freeing process stack trace to page owner info, if both page_owner and debug_pagealloc are configured and enabled. With only page_owner enabled, this info is not useful for the memory leak debugging use case. dump_page() is adjusted to print the info. An example result of calling __free_pages() twice may look like this (note the page last free stack trace): BUG: Bad page state in process bash pfn:13d8f8 page:ffffc31984f63e00 refcount:-1 mapcount:0 mapping:0000000000000000 index:0x0 flags: 0x1affff800000000() raw: 01affff800000000 dead000000000100 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000000000 ffffffffffffffff 0000000000000000 page dumped because: nonzero _refcount page_owner tracks the page as freed page last allocated via order 0, migratetype Unmovable, gfp_mask 0xcc0(GFP_KERNEL) prep_new_page+0x143/0x150 get_page_from_freelist+0x289/0x380 __alloc_pages_nodemask+0x13c/0x2d0 khugepaged+0x6e/0xc10 kthread+0xf9/0x130 ret_from_fork+0x3a/0x50 page last free stack trace: free_pcp_prepare+0x134/0x1e0 free_unref_page+0x18/0x90 khugepaged+0x7b/0xc10 kthread+0xf9/0x130 ret_from_fork+0x3a/0x50 Modules linked in: CPU: 3 PID: 271 Comm: bash Not tainted 5.3.0-rc4-2.g07a1a73-default+ #57 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58-prebuilt.qemu.org 04/01/2014 Call Trace: dump_stack+0x85/0xc0 bad_page.cold+0xba/0xbf rmqueue_pcplist.isra.0+0x6c5/0x6d0 rmqueue+0x2d/0x810 get_page_from_freelist+0x191/0x380 __alloc_pages_nodemask+0x13c/0x2d0 __get_free_pages+0xd/0x30 __pud_alloc+0x2c/0x110 copy_page_range+0x4f9/0x630 dup_mmap+0x362/0x480 dup_mm+0x68/0x110 copy_process+0x19e1/0x1b40 _do_fork+0x73/0x310 __x64_sys_clone+0x75/0x80 do_syscall_64+0x6e/0x1e0 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f10af854a10 ... Link: http://lkml.kernel.org/r/20190820131828.22684-5-vbabka@suse.cz Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Cc: Kirill A. Shutemov <kirill@shutemov.name> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-09-23Merge tag 'pci-v5.4-changes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci Pull PCI updates from Bjorn Helgaas: "Enumeration: - Consolidate _HPP/_HPX stuff in pci-acpi.c and simplify it (Krzysztof Wilczynski) - Fix incorrect PCIe device types and remove dev->has_secondary_link to simplify code that deals with upstream/downstream ports (Mika Westerberg) - After suspend, restore Resizable BAR size bits correctly for 1MB BARs (Sumit Saxena) - Enable PCI_MSI_IRQ_DOMAIN support for RISC-V (Wesley Terpstra) Virtualization: - Add ACS quirks for iProc PAXB (Abhinav Ratna), Amazon Annapurna Labs (Ali Saidi) - Move sysfs SR-IOV functions to iov.c (Kelsey Skunberg) - Remove group write permissions from sysfs sriov_numvfs, sriov_drivers_autoprobe (Kelsey Skunberg) Hotplug: - Simplify pciehp indicator control (Denis Efremov) Peer-to-peer DMA: - Allow P2P DMA between root ports for whitelisted bridges (Logan Gunthorpe) - Whitelist some Intel host bridges for P2P DMA (Logan Gunthorpe) - DMA map P2P DMA requests that traverse host bridge (Logan Gunthorpe) Amazon Annapurna Labs host bridge driver: - Add DT binding and controller driver (Jonathan Chocron) Hyper-V host bridge driver: - Fix hv_pci_dev->pci_slot use-after-free (Dexuan Cui) - Fix PCI domain number collisions (Haiyang Zhang) - Use instance ID bytes 4 & 5 as PCI domain numbers (Haiyang Zhang) - Fix build errors on non-SYSFS config (Randy Dunlap) i.MX6 host bridge driver: - Limit DBI register length (Stefan Agner) Intel VMD host bridge driver: - Fix config addressing issues (Jon Derrick) Layerscape host bridge driver: - Add bar_fixed_64bit property to endpoint driver (Xiaowei Bao) - Add CONFIG_PCI_LAYERSCAPE_EP to build EP/RC drivers separately (Xiaowei Bao) Mediatek host bridge driver: - Add MT7629 controller support (Jianjun Wang) Mobiveil host bridge driver: - Fix CPU base address setup (Hou Zhiqiang) - Make "num-lanes" property optional (Hou Zhiqiang) Tegra host bridge driver: - Fix OF node reference leak (Nishka Dasgupta) - Disable MSI for root ports to work around design problem (Vidya Sagar) - Add Tegra194 DT binding and controller support (Vidya Sagar) - Add support for sideband pins and slot regulators (Vidya Sagar) - Add PIPE2UPHY support (Vidya Sagar) Misc: - Remove unused pci_block_cfg_access() et al (Kelsey Skunberg) - Unexport pci_bus_get(), etc (Kelsey Skunberg) - Hide PM, VC, link speed, ATS, ECRC, PTM constants and interfaces in the PCI core (Kelsey Skunberg) - Clean up sysfs DEVICE_ATTR() usage (Kelsey Skunberg) - Mark expected switch fall-through (Gustavo A. R. Silva) - Propagate errors for optional regulators and PHYs (Thierry Reding) - Fix kernel command line resource_alignment parameter issues (Logan Gunthorpe)" * tag 'pci-v5.4-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (112 commits) PCI: Add pci_irq_vector() and other stubs when !CONFIG_PCI arm64: tegra: Add PCIe slot supply information in p2972-0000 platform arm64: tegra: Add configuration for PCIe C5 sideband signals PCI: tegra: Add support to enable slot regulators PCI: tegra: Add support to configure sideband pins PCI: vmd: Fix shadow offsets to reflect spec changes PCI: vmd: Fix config addressing when using bus offsets PCI: dwc: Add validation that PCIe core is set to correct mode PCI: dwc: al: Add Amazon Annapurna Labs PCIe controller driver dt-bindings: PCI: Add Amazon's Annapurna Labs PCIe host bridge binding PCI: Add quirk to disable MSI-X support for Amazon's Annapurna Labs Root Port PCI/VPD: Prevent VPD access for Amazon's Annapurna Labs Root Port PCI: Add ACS quirk for Amazon Annapurna Labs root ports PCI: Add Amazon's Annapurna Labs vendor ID MAINTAINERS: Add PCI native host/endpoint controllers designated reviewer PCI: hv: Use bytes 4 and 5 from instance ID as the PCI domain numbers dt-bindings: PCI: tegra: Add PCIe slot supplies regulator entries dt-bindings: PCI: tegra: Add sideband pins configuration entries PCI: tegra: Add Tegra194 PCIe support PCI: Get rid of dev->has_secondary_link flag ...
2019-09-20Merge tag 'powerpc-5.4-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: "This is a bit late, partly due to me travelling, and partly due to a power outage knocking out some of my test systems *while* I was travelling. - Initial support for running on a system with an Ultravisor, which is software that runs below the hypervisor and protects guests against some attacks by the hypervisor. - Support for building the kernel to run as a "Secure Virtual Machine", ie. as a guest capable of running on a system with an Ultravisor. - Some changes to our DMA code on bare metal, to allow devices with medium sized DMA masks (> 32 && < 59 bits) to use more than 2GB of DMA space. - Support for firmware assisted crash dumps on bare metal (powernv). - Two series fixing bugs in and refactoring our PCI EEH code. - A large series refactoring our exception entry code to use gas macros, both to make it more readable and also enable some future optimisations. As well as many cleanups and other minor features & fixups. Thanks to: Adam Zerella, Alexey Kardashevskiy, Alistair Popple, Andrew Donnellan, Aneesh Kumar K.V, Anju T Sudhakar, Anshuman Khandual, Balbir Singh, Benjamin Herrenschmidt, Cédric Le Goater, Christophe JAILLET, Christophe Leroy, Christopher M. Riedl, Christoph Hellwig, Claudio Carvalho, Daniel Axtens, David Gibson, David Hildenbrand, Desnes A. Nunes do Rosario, Ganesh Goudar, Gautham R. Shenoy, Greg Kurz, Guerney Hunt, Gustavo Romero, Halil Pasic, Hari Bathini, Joakim Tjernlund, Jonathan Neuschafer, Jordan Niethe, Leonardo Bras, Lianbo Jiang, Madhavan Srinivasan, Mahesh Salgaonkar, Mahesh Salgaonkar, Masahiro Yamada, Maxiwell S. Garcia, Michael Anderson, Nathan Chancellor, Nathan Lynch, Naveen N. Rao, Nicholas Piggin, Oliver O'Halloran, Qian Cai, Ram Pai, Ravi Bangoria, Reza Arbab, Ryan Grimm, Sam Bobroff, Santosh Sivaraj, Segher Boessenkool, Sukadev Bhattiprolu, Thiago Bauermann, Thiago Jung Bauermann, Thomas Gleixner, Tom Lendacky, Vasant Hegde" * tag 'powerpc-5.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (264 commits) powerpc/mm/mce: Keep irqs disabled during lockless page table walk powerpc: Use ftrace_graph_ret_addr() when unwinding powerpc/ftrace: Enable HAVE_FUNCTION_GRAPH_RET_ADDR_PTR ftrace: Look up the address of return_to_handler() using helpers powerpc: dump kernel log before carrying out fadump or kdump docs: powerpc: Add missing documentation reference powerpc/xmon: Fix output of XIVE IPI powerpc/xmon: Improve output of XIVE interrupts powerpc/mm/radix: remove useless kernel messages powerpc/fadump: support holes in kernel boot memory area powerpc/fadump: remove RMA_START and RMA_END macros powerpc/fadump: update documentation about option to release opalcore powerpc/fadump: consider f/w load area powerpc/opalcore: provide an option to invalidate /sys/firmware/opal/core file powerpc/opalcore: export /sys/firmware/opal/core for analysing opal crashes powerpc/fadump: update documentation about CONFIG_PRESERVE_FA_DUMP powerpc/fadump: add support to preserve crash data on FADUMP disabled kernel powerpc/fadump: improve how crashed kernel's memory is reserved powerpc/fadump: consider reserved ranges while releasing memory powerpc/fadump: make crash memory ranges array allocation generic ...
2019-09-18Merge tag 'tty-5.4-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty Pull tty/serial driver updates from Greg KH: "Even in this age, people are still making new serial port silicon, why... Anyway, here's the TTY and Serial driver update for 5.4-rc1. Lots of changes in here for a number of embedded serial port devices that are being worked on because people really like to see those console logs... Other than that, nothing major here, no core tty changes that anyone should care about. All of these have been in linux-next for a while with no reported issues" * tag 'tty-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (125 commits) serial: tegra: Add PIO mode support serial: tegra: report clk rate errors serial: tegra: add support to adjust baud rate serial: tegra: DT for Adjusted baud rates serial: tegra: add support to use 8 bytes trigger serial: tegra: set maximum num of uart ports to 8 serial: tegra: check for FIFO mode enabled status dt-binding: serial: tegra: add new chips serial: tegra: report error to upper tty layer serial: tegra: flush the RX fifo on frame error serial: tegra: avoid reg access when clk disabled serial: tegra: add support to ignore read serial: sprd: correct the wrong sequence of arguments dt-bindings: serial: Convert riscv,sifive-serial to json-schema serial: max310x: turn off transmitter before activating AutoCTS or auto transmitter flow control serial: max310x: Properly set flags in AutoCTS mode tty: serial: fix platform_no_drv_owner.cocci warnings dt-bindings: serial: Document Freescale LINFlexD UART serial: fsl_linflexuart: Update compatible string tty: n_gsm: avoid recursive locking with async port hangup ...
2019-09-17Merge tag 'for-5.4/block-2019-09-16' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block updates from Jens Axboe: - Two NVMe pull requests: - ana log parse fix from Anton - nvme quirks support for Apple devices from Ben - fix missing bio completion tracing for multipath stack devices from Hannes and Mikhail - IP TOS settings for nvme rdma and tcp transports from Israel - rq_dma_dir cleanups from Israel - tracing for Get LBA Status command from Minwoo - Some nvme-tcp cleanups from Minwoo, Potnuri and Myself - Some consolidation between the fabrics transports for handling the CAP register - reset race with ns scanning fix for fabrics (move fabrics commands to a dedicated request queue with a different lifetime from the admin request queue)." - controller reset and namespace scan races fixes - nvme discovery log change uevent support - naming improvements from Keith - multiple discovery controllers reject fix from James - some regular cleanups from various people - Series fixing (and re-fixing) null_blk debug printing and nr_devices checks (André) - A few pull requests from Song, with fixes from Andy, Guoqing, Guilherme, Neil, Nigel, and Yufen. - REQ_OP_ZONE_RESET_ALL support (Chaitanya) - Bio merge handling unification (Christoph) - Pick default elevator correctly for devices with special needs (Damien) - Block stats fixes (Hou) - Timeout and support devices nbd fixes (Mike) - Series fixing races around elevator switching and device add/remove (Ming) - sed-opal cleanups (Revanth) - Per device weight support for BFQ (Fam) - Support for blk-iocost, a new model that can properly account cost of IO workloads. (Tejun) - blk-cgroup writeback fixes (Tejun) - paride queue init fixes (zhengbin) - blk_set_runtime_active() cleanup (Stanley) - Block segment mapping optimizations (Bart) - lightnvm fixes (Hans/Minwoo/YueHaibing) - Various little fixes and cleanups * tag 'for-5.4/block-2019-09-16' of git://git.kernel.dk/linux-block: (186 commits) null_blk: format pr_* logs with pr_fmt null_blk: match the type of parameter nr_devices null_blk: do not fail the module load with zero devices block: also check RQF_STATS in blk_mq_need_time_stamp() block: make rq sector size accessible for block stats bfq: Fix bfq linkage error raid5: use bio_end_sector in r5_next_bio raid5: remove STRIPE_OPS_REQ_PENDING md: add feature flag MD_FEATURE_RAID0_LAYOUT md/raid0: avoid RAID0 data corruption due to layout confusion. raid5: don't set STRIPE_HANDLE to stripe which is in batch list raid5: don't increment read_errors on EILSEQ return nvmet: fix a wrong error status returned in error log page nvme: send discovery log page change events to userspace nvme: add uevent variables for controller devices nvme: enable aen regardless of the presence of I/O queues nvme-fabrics: allow discovery subsystems accept a kato nvmet: Use PTR_ERR_OR_ZERO() in nvmet_init_discovery() nvme: Remove redundant assignment of cq vector nvme: Assign subsys instance from first ctrl ...
2019-09-17Merge tag 'docs-5.4' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation updates from Jonathan Corbet: "It's a somewhat calmer cycle for docs this time, as the churn of the mass RST conversion is happily mostly behind us. - A new document on reproducible builds. - We finally got around to zapping the documentation for hardware support that was removed in 2004; one doesn't want to rush these things. - The usual assortment of fixes, typo corrections, etc" * tag 'docs-5.4' of git://git.lwn.net/linux: (67 commits) Documentation: kbuild: Add document about reproducible builds docs: printk-formats: Stop encouraging use of unnecessary %h[xudi] and %hh[xudi] Documentation: Add "earlycon=sbi" to the admin guide doc:lock: remove reference to clever use of read-write lock devices.txt: improve entry for comedi (char major 98) docs: mtd: Update spi nor reference driver doc: arm64: fix grammar dtb placed in no attributes region Documentation: sysrq: don't recommend 'S' 'U' before 'B' mailmap: Update email address for Quentin Perret docs: ftrace: clarify when tracing is disabled by the trace file docs: process: fix broken link Documentation/arm/samsung-s3c24xx: Remove stray U+FEFF character to fix title Documentation/arm/sa1100/assabet: Fix 'make assabet_defconfig' command Documentation/arm/sa1100: Remove some obsolete documentation docs/zh_CN: update Chinese howto.rst for latexdocs making Documentation: virt: Fix broken reference to virt tree's index docs: Fix typo on pull requests guide kernel-doc: Allow anonymous enum Documentation: sphinx: Don't parse socket() as identifier reference Documentation: sphinx: Add missing comma to list of strings ...
2019-09-16Merge branch 'core-rcu-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull RCU updates from Ingo Molnar: "This cycle's RCU changes were: - A few more RCU flavor consolidation cleanups. - Updates to RCU's list-traversal macros improving lockdep usability. - Forward-progress improvements for no-CBs CPUs: Avoid ignoring incoming callbacks during grace-period waits. - Forward-progress improvements for no-CBs CPUs: Use ->cblist structure to take advantage of others' grace periods. - Also added a small commit that avoids needlessly inflicting scheduler-clock ticks on callback-offloaded CPUs. - Forward-progress improvements for no-CBs CPUs: Reduce contention on ->nocb_lock guarding ->cblist. - Forward-progress improvements for no-CBs CPUs: Add ->nocb_bypass list to further reduce contention on ->nocb_lock guarding ->cblist. - Miscellaneous fixes. - Torture-test updates. - minor LKMM updates" * 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (86 commits) MAINTAINERS: Update from paulmck@linux.ibm.com to paulmck@kernel.org rcu: Don't include <linux/ktime.h> in rcutiny.h rcu: Allow rcu_do_batch() to dynamically adjust batch sizes rcu/nocb: Don't wake no-CBs GP kthread if timer posted under overload rcu/nocb: Reduce __call_rcu_nocb_wake() leaf rcu_node ->lock contention rcu/nocb: Reduce nocb_cb_wait() leaf rcu_node ->lock contention rcu/nocb: Advance CBs after merge in rcutree_migrate_callbacks() rcu/nocb: Avoid synchronous wakeup in __call_rcu_nocb_wake() rcu/nocb: Print no-CBs diagnostics when rcutorture writer unduly delayed rcu/nocb: EXP Check use and usefulness of ->nocb_lock_contended rcu/nocb: Add bypass callback queueing rcu/nocb: Atomic ->len field in rcu_segcblist structure rcu/nocb: Unconditionally advance and wake for excessive CBs rcu/nocb: Reduce ->nocb_lock contention with separate ->nocb_gp_lock rcu/nocb: Reduce contention at no-CBs invocation-done time rcu/nocb: Reduce contention at no-CBs registry-time CB advancement rcu/nocb: Round down for number of no-CBs grace-period kthreads rcu/nocb: Avoid ->nocb_lock capture by corresponding CPU rcu/nocb: Avoid needless wakeups of no-CBs grace-period kthread rcu/nocb: Make __call_rcu_nocb_wake() safe for many callbacks ...
2019-09-16Merge tag 'please-pull-ia64_for_5.4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux Pull ia64 updates from Tony Luck: "The big change here is removal of support for SGI Altix" * tag 'please-pull-ia64_for_5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux: (33 commits) genirq: remove the is_affinity_mask_valid hook ia64: remove CONFIG_SWIOTLB ifdefs ia64: remove support for machvecs ia64: move the screen_info setup to common code ia64: move the ROOT_DEV setup to common code ia64: rework iommu probing ia64: remove the unused sn_coherency_id symbol ia64: remove the SGI UV simulator support ia64: remove the zx1 swiotlb machvec ia64: remove CONFIG_ACPI ifdefs ia64: remove CONFIG_PCI ifdefs ia64: remove the hpsim platform ia64: remove now unused machvec indirections ia64: remove support for the SGI SN2 platform drivers: remove the SGI SN2 IOC4 base support drivers: remove the SGI SN2 IOC3 base support qla2xxx: remove SGI SN2 support qla1280: remove SGI SN2 support misc/sgi-xp: remove SGI SN2 support char/mspec: remove SGI SN2 support ...
2019-09-14Documentation: Add "earlycon=sbi" to the admin guidePalmer Dabbelt
This argument is supported on RISC-V systems and widely used, but was not documented here. Signed-off-by: Palmer Dabbelt <palmer@sifive.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-09-11Merge branches 'arm/omap', 'arm/exynos', 'arm/smmu', 'arm/mediatek', ↵Joerg Roedel
'arm/qcom', 'arm/renesas', 'x86/amd', 'x86/vt-d' and 'core' into next
2019-09-11iommu/vt-d: Check whether device requires bounce bufferLu Baolu
This adds a helper to check whether a device needs to use bounce buffer. It also provides a boot time option to disable the bounce buffer. Users can use this to prevent the iommu driver from using the bounce buffer for performance gain. Cc: Ashok Raj <ashok.raj@intel.com> Cc: Jacob Pan <jacob.jun.pan@linux.intel.com> Cc: Kevin Tian <kevin.tian@intel.com> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Tested-by: Xu Pengfei <pengfei.xu@intel.com> Tested-by: Mika Westerberg <mika.westerberg@intel.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-09-05powerpc/64s/radix: introduce options to disable use of the tlbie instructionNicholas Piggin
Introduce two options to control the use of the tlbie instruction. A boot time option which completely disables the kernel using the instruction, this is currently incompatible with HASH MMU, KVM, and coherent accelerators. And a debugfs option can be switched at runtime and avoids using tlbie for invalidating CPU TLBs for normal process and kernel address mappings. Coherent accelerators are still managed with tlbie, as will KVM partition scope translations. Cross-CPU TLB flushing is implemented with IPIs and tlbiel. This is a basic implementation which does not attempt to make any optimisation beyond the tlbie implementation. This is useful for performance testing among other things. For example in certain situations on large systems, using IPIs may be faster than tlbie as they can be directed rather than broadcast. Later we may also take advantage of the IPIs to do more interesting things such as trim the mm cpumask more aggressively. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190902152931.17840-7-npiggin@gmail.com
2019-09-04tty: serial: Add linflexuart driver for S32V234Stefan-gabriel Mirea
Introduce support for LINFlex driver, based on: - the version of Freescale LPUART driver after commit b3e3bf2ef2c7 ("Merge 4.0-rc7 into tty-next"); - commit abf1e0a98083 ("tty: serial: fsl_lpuart: lock port on console write"). In this basic version, the driver can be tested using initramfs and relies on the clocks and pin muxing set up by U-Boot. Remarks concerning the earlycon support: - LinFlexD does not allow character transmissions in the INIT mode (see section 47.4.2.1 in the reference manual[1]). Therefore, a mutual exclusion between the first linflex_setup_watermark/linflex_set_termios executions and linflex_earlycon_putchar was employed and the characters normally sent to earlycon during initialization are kept in a buffer and sent afterwards. - Empirically, character transmission is also forbidden within the last 1-2 ms before entering the INIT mode, so we use an explicit timeout (PREINIT_DELAY) between linflex_earlycon_putchar and the first call to linflex_setup_watermark. - U-Boot currently uses the UART FIFO mode, while this driver makes the transition to the buffer mode. Therefore, the earlycon putchar function matches the U-Boot behavior before initializations and the Linux behavior after. [1] https://www.nxp.com/webapp/Download?colCode=S32V234RM Signed-off-by: Stoica Cosmin-Stefan <cosmin.stoica@nxp.com> Signed-off-by: Adrian.Nitu <adrian.nitu@freescale.com> Signed-off-by: Larisa Grigore <Larisa.Grigore@nxp.com> Signed-off-by: Ana Nedelcu <B56683@freescale.com> Signed-off-by: Mihaela Martinas <Mihaela.Martinas@freescale.com> Signed-off-by: Matthew Nunez <matthew.nunez@nxp.com> [stefan-gabriel.mirea@nxp.com: Reduced for upstreaming and implemented earlycon support] Signed-off-by: Stefan-Gabriel Mirea <stefan-gabriel.mirea@nxp.com> Link: https://lore.kernel.org/r/20190809112853.15846-6-stefan-gabriel.mirea@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-03block: elevator.c: Remove now unused elevator= argumentMarcos Paulo de Souza
Since the inclusion of blk-mq, elevator argument was not being considered anymore, and it's utility died long with the legacy IO path, now removed too. Reviewed-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Bob Liu <bob.liu@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Marcos Paulo de Souza <marcos.souza.org@gmail.com> Fold with doc removal patch. Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-08-30powerpc/prom_init: Add the ESM call to prom_initRam Pai
Make the Enter-Secure-Mode (ESM) ultravisor call to switch the VM to secure mode. Pass kernel base address and FDT address so that the Ultravisor is able to verify the integrity of the VM using information from the ESM blob. Add "svm=" command line option to turn on switching to secure mode. Signed-off-by: Ram Pai <linuxram@us.ibm.com> [ andmike: Generate an RTAS os-term hcall when the ESM ucall fails. ] Signed-off-by: Michael Anderson <andmike@linux.ibm.com> [ bauerman: Cleaned up the code a bit. ] Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190820021326.6884-5-bauerman@linux.ibm.com
2019-08-23Documentation: Update Documentation for iommu.passthroughJoerg Roedel
This kernel parameter now takes also effect on X86. Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-08-22Merge branch 'for-mingo' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu Pull RCU and LKMM changes from Paul E. McKenney: - A few more RCU flavor consolidation cleanups. - Miscellaneous fixes. - Updates to RCU's list-traversal macros improving lockdep usability. - Torture-test updates. - Forward-progress improvements for no-CBs CPUs: Avoid ignoring incoming callbacks during grace-period waits. - Forward-progress improvements for no-CBs CPUs: Use ->cblist structure to take advantage of others' grace periods. - Also added a small commit that avoids needlessly inflicting scheduler-clock ticks on callback-offloaded CPUs. - Forward-progress improvements for no-CBs CPUs: Reduce contention on ->nocb_lock guarding ->cblist. - Forward-progress improvements for no-CBs CPUs: Add ->nocb_bypass list to further reduce contention on ->nocb_lock guarding ->cblist. - LKMM updates. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-08-22powerpc: Document xmon optionsGustavo Romero
Document all options currently supported by xmon debugger. Signed-off-by: Gustavo Romero <gromero@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190814205638.25322-1-gromero@linux.ibm.com
2019-08-19security: Add a static lockdown policy LSMMatthew Garrett
While existing LSMs can be extended to handle lockdown policy, distributions generally want to be able to apply a straightforward static policy. This patch adds a simple LSM that can be configured to reject either integrity or all lockdown queries, and can be configured at runtime (through securityfs), boot time (via a kernel parameter) or build time (via a kconfig option). Based on initial code by David Howells. Signed-off-by: Matthew Garrett <mjg59@google.com> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: David Howells <dhowells@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2019-08-19x86/CPU/AMD: Clear RDRAND CPUID bit on AMD family 15h/16hTom Lendacky
There have been reports of RDRAND issues after resuming from suspend on some AMD family 15h and family 16h systems. This issue stems from a BIOS not performing the proper steps during resume to ensure RDRAND continues to function properly. RDRAND support is indicated by CPUID Fn00000001_ECX[30]. This bit can be reset by clearing MSR C001_1004[62]. Any software that checks for RDRAND support using CPUID, including the kernel, will believe that RDRAND is not supported. Update the CPU initialization to clear the RDRAND CPUID bit for any family 15h and 16h processor that supports RDRAND. If it is known that the family 15h or family 16h system does not have an RDRAND resume issue or that the system will not be placed in suspend, the "rdrand=force" kernel parameter can be used to stop the clearing of the RDRAND CPUID bit. Additionally, update the suspend and resume path to save and restore the MSR C001_1004 value to ensure that the RDRAND CPUID setting remains in place after resuming from suspend. Note, that clearing the RDRAND CPUID bit does not prevent a processor that normally supports the RDRAND instruction from executing it. So any code that determined the support based on family and model won't #UD. Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andrew Cooper <andrew.cooper3@citrix.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Chen Yu <yu.c.chen@intel.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Kees Cook <keescook@chromium.org> Cc: "linux-doc@vger.kernel.org" <linux-doc@vger.kernel.org> Cc: "linux-pm@vger.kernel.org" <linux-pm@vger.kernel.org> Cc: Nathan Chancellor <natechancellor@gmail.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: <stable@vger.kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "x86@kernel.org" <x86@kernel.org> Link: https://lkml.kernel.org/r/7543af91666f491547bd86cebb1e17c66824ab9f.1566229943.git.thomas.lendacky@amd.com
2019-08-16ia64: remove the zx1 swiotlb machvecChristoph Hellwig
The aim of this machvec is to support devices with < 32-bit dma masks. But given that ia64 only has a ZONE_DMA32 and not a ZONE_DMA that isn't supported by swiotlb either. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lkml.kernel.org/r/20190813072514.23299-21-hch@lst.de Signed-off-by: Tony Luck <tony.luck@intel.com>
2019-08-13rcu/nocb: Rename rcu_nocb_leader_stride kernel boot parameterPaul E. McKenney
This commit changes the name of the rcu_nocb_leader_stride kernel boot parameter to rcu_nocb_gp_stride in order to account for the new distinction between callback and grace-period no-CBs kthreads. Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-08-08PCI: Correct pci=resource_alignment parameter exampleAlexey Kardashevskiy
The "pci=resource_alignment" parameter is described as requiring an order (not a size) and the code in pci_specified_resource_alignment() expects an order. But the example wrongly shows a size. Convert the example to an order. Fixes: 8b078c603249 ("PCI: Update "pci=resource_alignment" documentation") Link: https://lore.kernel.org/r/20190606032557.107542-1-aik@ozlabs.ru Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>