summaryrefslogtreecommitdiff
path: root/arch/x86/xen
AgeCommit message (Collapse)AuthorFilesLines
2023-08-29Merge tag 'acpi-6.6-rc1' of ↵Linus Torvalds1-4/+4
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull ACPI updates from Rafael Wysocki: "These include new ACPICA material, a rework of the ACPI thermal driver, a switch-over of the ACPI processor driver to using _OSC instead of (long deprecated) _PDC for CPU initialization, a rework of firmware notifications handling in several drivers, fixes and cleanups for suspend-to-idle handling on AMD systems, ACPI backlight driver updates and more. Specifics: - Update the ACPICA code in the kernel to upstream revision 20230628 including the following changes: - Suppress a GCC 12 dangling-pointer warning (Philip Prindeville) - Reformat the ACPI_STATE_COMMON macro and its users (George Guo) - Replace the ternary operator with ACPI_MIN() (Jiangshan Yi) - Add support for _DSC as per ACPI 6.5 (Saket Dumbre) - Remove a duplicate macro from zephyr header (Najumon B.A) - Add data structures for GED and _EVT tracking (Jose Marinho) - Fix misspelled CDAT DSMAS define (Dave Jiang) - Simplify an error message in acpi_ds_result_push() (Christophe Jaillet) - Add a struct size macro related to SRAT (Dave Jiang) - Add AML_NO_OPERAND_RESOLVE flag to Timer (Abhishek Mainkar) - Add support for RISC-V external interrupt controllers in MADT (Sunil V L) - Add RHCT flags, CMO and MMU nodes (Sunil V L) - Change ACPICA version to 20230628 (Bob Moore) - Introduce new wrappers for ACPICA notify handler install/remove and convert multiple drivers to using their own Notify() handlers instead of the ACPI bus type .notify() slated for removal (Michal Wilczynski) - Add backlight=native DMI quirk for Apple iMac12,1 and iMac12,2 (Hans de Goede) - Put ACPI video and its child devices explicitly into D0 on boot to avoid platform firmware confusion (Kai-Heng Feng) - Add backlight=native DMI quirk for Lenovo Ideapad Z470 (Jiri Slaby) - Support obtaining physical CPU ID from MADT on LoongArch (Bibo Mao) - Convert ACPI CPU initialization to using _OSC instead of _PDC that has been depreceted since 2018 and dropped from the specification in ACPI 6.5 (Michal Wilczynski, Rafael Wysocki) - Drop non-functional nocrt parameter from ACPI thermal (Mario Limonciello) - Clean up the ACPI thermal driver, rework the handling of firmware notifications in it and make it provide a table of generic trip point structures to the core during initialization (Rafael Wysocki) - Defer enumeration of devices with _DEP pointing to IVSC (Wentong Wu) - Install SystemCMOS address space handler for ACPI000E (TAD) to meet platform firmware expectations on some platforms (Zhang Rui) - Fix finding the generic error data in the ACPi extlog driver for compatibility with old and new firmware interface versions (Xiaochun Lee) - Remove assorted unused declarations of functions (Yue Haibing) - Move AMBA bus scan handling into arm64 specific directory (Sudeep Holla) - Fix and clean up suspend-to-idle interface for AMD systems (Mario Limonciello, Andy Shevchenko) - Fix string truncation warning in pnpacpi_add_device() (Sunil V L)" * tag 'acpi-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (66 commits) ACPI: x86: s2idle: Add a function to get LPS0 constraint for a device ACPI: x86: s2idle: Add for_each_lpi_constraint() helper ACPI: x86: s2idle: Add more debugging for AMD constraints parsing ACPI: x86: s2idle: Fix a logic error parsing AMD constraints table ACPI: x86: s2idle: Catch multiple ACPI_TYPE_PACKAGE objects ACPI: x86: s2idle: Post-increment variables when getting constraints ACPI: Adjust #ifdef for *_lps0_dev use ACPI: TAD: Install SystemCMOS address space handler for ACPI000E ACPI: Remove assorted unused declarations of functions ACPI: extlog: Fix finding the generic error data for v3 structure PNP: ACPI: Fix string truncation warning ACPI: Remove unused extern declaration acpi_paddr_to_node() ACPI: video: Add backlight=native DMI quirk for Apple iMac12,1 and iMac12,2 ACPI: video: Put ACPI video and its child devices into D0 on boot ACPI: processor: LoongArch: Get physical ID from MADT ACPI: scan: Defer enumeration of devices with a _DEP pointing to IVSC device ACPI: thermal: Eliminate code duplication from acpi_thermal_notify() ACPI: thermal: Drop unnecessary thermal zone callbacks ACPI: thermal: Rework thermal_get_trend() ACPI: thermal: Use trip point table to register thermal zones ...
2023-08-25Merge branch 'acpi-processor'Rafael J. Wysocki1-4/+4
Merge ACPI processor driver changes for 6.6-rc1: - Support obtaining physical CPU ID from MADT on LoongArch (Bibo Mao). - Convert ACPI CPU initialization to using _OSC instead of _PDC that has been depreceted since 2018 and dropped from the specification in ACPI 6.5 (Michal Wilczynski, Rafael Wysocki). * acpi-processor: ACPI: processor: LoongArch: Get physical ID from MADT ACPI: processor: Refine messages in acpi_early_processor_control_setup() ACPI: processor: Remove acpi_hwp_native_thermal_lvt_osc() ACPI: processor: Use _OSC to convey OSPM processor support information ACPI: processor: Introduce acpi_processor_osc() ACPI: processor: Set CAP_SMP_T_SWCOORD in arch_acpi_set_proc_cap_bits() ACPI: processor: Clear C_C2C3_FFH and C_C1_FFH in arch_acpi_set_proc_cap_bits() ACPI: processor: Rename ACPI_PDC symbols ACPI: processor: Refactor arch_acpi_set_pdc_bits() ACPI: processor: Move processor_physically_present() to acpi_processor.c ACPI: processor: Move MWAIT quirk out of acpi_processor.c
2023-08-21x86/xen: Make virt_to_pfn() a static inlineLinus Walleij3-9/+9
Making virt_to_pfn() a static inline taking a strongly typed (const void *) makes the contract of a passing a pointer of that type to the function explicit and exposes any misuse of the macro virt_to_pfn() acting polymorphic and accepting many types such as (void *), (unitptr_t) or (unsigned long) as arguments without warnings. Also fix all offending call sites to pass a (void *) rather than an unsigned long. Since virt_to_mfn() is wrapping virt_to_pfn() this function has become polymorphic as well so the usage need to be fixed up. Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/20230810-virt-to-phys-x86-xen-v1-1-9e966d333e7a@linaro.org Signed-off-by: Juergen Gross <jgross@suse.com>
2023-08-21xen: remove a confusing comment on auto-translated guest I/OPetr Tesarik1-6/+0
After removing the conditional return from xen_create_contiguous_region(), the accompanying comment was left in place, but it now precedes an unrelated conditional and confuses readers. Fixes: 989513a735f5 ("xen: cleanup pvh leftovers from pv-only sources") Signed-off-by: Petr Tesarik <petr.tesarik.ext@huawei.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lore.kernel.org/r/20230802163151.1486-1-petrtesarik@huaweicloud.com Signed-off-by: Juergen Gross <jgross@suse.com>
2023-07-14ACPI: processor: Rename ACPI_PDC symbolsMichal Wilczynski1-4/+4
The prefix in the names of the ACPI_PDC symbols suggests that they are only relevant for _PDC, but in fact they can also be used in the _OSC. Change that prefix to a more generic ACPI_PROC_CAP that will better reflect the purpose of those symbols as they represent bits in a general processor capabilities buffer. Rename pdc_intel.h to proc_cap_intel.h to follow the change of the symbol name prefix. No intentional functional impact. Suggested-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Michal Wilczynski <michal.wilczynski@intel.com> [ rjw: Subject and changelog edits ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2023-07-13Merge tag 'for-linus-6.5-rc2-tag' of ↵Linus Torvalds1-16/+21
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen fixes from Juergen Gross: - a cleanup of the Xen related ELF-notes - a fix for virtio handling in Xen dom0 when running Xen in a VM * tag 'for-linus-6.5-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen/virtio: Fix NULL deref when a bridge of PCI root bus has no parent x86/Xen: tidy xen-head.S
2023-07-09Merge tag 'x86_urgent_for_v6.5_rc1' of ↵Linus Torvalds1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fpu fix from Borislav Petkov: - Do FPU AP initialization on Xen PV too which got missed by the recent boot reordering work * tag 'x86_urgent_for_v6.5_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/xen: Fix secondary processors' FPU initialization
2023-07-05x86/xen: Fix secondary processors' FPU initializationJuergen Gross1-0/+1
Moving the call of fpu__init_cpu() from cpu_init() to start_secondary() broke Xen PV guests, as those don't call start_secondary() for APs. Call fpu__init_cpu() in Xen's cpu_bringup(), which is the Xen PV replacement of start_secondary(). Fixes: b81fac906a8f ("x86/fpu: Move FPU initialization into arch_cpu_finalize_init()") Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20230703130032.22916-1-jgross@suse.com
2023-07-04x86/Xen: tidy xen-head.SJan Beulich1-16/+21
First of all move PV-only ELF notes inside the XEN_PV conditional; note that - HV_START_LOW is dropped altogether, as it was meaningful for 32-bit PV only, - the 32-bit instance of VIRT_BASE is dropped, as it would be dead code once inside the conditional, - while PADDR_OFFSET is not exactly unused for PVH, it defaults to zero there, and the hypervisor (or tool stack) complains if it is present but VIRT_BASE isn't. Then have the "supported features" note actually report reality: All three of the features there are supported and/or applicable only in certain cases. Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/f99bacc6-2a2f-41b0-5c0b-e01b7051cb07@suse.com Signed-off-by: Juergen Gross <jgross@suse.com>
2023-06-28Merge tag 'for-linus-6.5-rc1-tag' of ↵Linus Torvalds6-12/+44
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen updates from Juergen Gross: - three patches adding missing prototypes - a fix for finding the iBFT in a Xen dom0 for supporting diskless iSCSI boot * tag 'for-linus-6.5-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: x86: xen: add missing prototypes x86/xen: add prototypes for paravirt mmu functions iscsi_ibft: Fix finding the iBFT under Xen Dom 0 xen: xen_debug_interrupt prototype to global header
2023-06-28Merge tag 'sched-core-2023-06-27' of ↵Linus Torvalds1-2/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Ingo Molnar: "Scheduler SMP load-balancer improvements: - Avoid unnecessary migrations within SMT domains on hybrid systems. Problem: On hybrid CPU systems, (processors with a mixture of higher-frequency SMT cores and lower-frequency non-SMT cores), under the old code lower-priority CPUs pulled tasks from the higher-priority cores if more than one SMT sibling was busy - resulting in many unnecessary task migrations. Solution: The new code improves the load balancer to recognize SMT cores with more than one busy sibling and allows lower-priority CPUs to pull tasks, which avoids superfluous migrations and lets lower-priority cores inspect all SMT siblings for the busiest queue. - Implement the 'runnable boosting' feature in the EAS balancer: consider CPU contention in frequency, EAS max util & load-balance busiest CPU selection. This improves CPU utilization for certain workloads, while leaves other key workloads unchanged. Scheduler infrastructure improvements: - Rewrite the scheduler topology setup code by consolidating it into the build_sched_topology() helper function and building it dynamically on the fly. - Resolve the local_clock() vs. noinstr complications by rewriting the code: provide separate sched_clock_noinstr() and local_clock_noinstr() functions to be used in instrumentation code, and make sure it is all instrumentation-safe. Fixes: - Fix a kthread_park() race with wait_woken() - Fix misc wait_task_inactive() bugs unearthed by the -rt merge: - Fix UP PREEMPT bug by unifying the SMP and UP implementations - Fix task_struct::saved_state handling - Fix various rq clock update bugs, unearthed by turning on the rq clock debugging code. - Fix the PSI WINDOW_MIN_US trigger limit, which was easy to trigger by creating enough cgroups, by removing the warnign and restricting window size triggers to PSI file write-permission or CAP_SYS_RESOURCE. - Propagate SMT flags in the topology when removing degenerate domain - Fix grub_reclaim() calculation bug in the deadline scheduler code - Avoid resetting the min update period when it is unnecessary, in psi_trigger_destroy(). - Don't balance a task to its current running CPU in load_balance(), which was possible on certain NUMA topologies with overlapping groups. - Fix the sched-debug printing of rq->nr_uninterruptible Cleanups: - Address various -Wmissing-prototype warnings, as a preparation to (maybe) enable this warning in the future. - Remove unused code - Mark more functions __init - Fix shadow-variable warnings" * tag 'sched-core-2023-06-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (50 commits) sched/core: Avoid multiple calling update_rq_clock() in __cfsb_csd_unthrottle() sched/core: Avoid double calling update_rq_clock() in __balance_push_cpu_stop() sched/core: Fixed missing rq clock update before calling set_rq_offline() sched/deadline: Update GRUB description in the documentation sched/deadline: Fix bandwidth reclaim equation in GRUB sched/wait: Fix a kthread_park race with wait_woken() sched/topology: Mark set_sched_topology() __init sched/fair: Rename variable cpu_util eff_util arm64/arch_timer: Fix MMIO byteswap sched/fair, cpufreq: Introduce 'runnable boosting' sched/fair: Refactor CPU utilization functions cpuidle: Use local_clock_noinstr() sched/clock: Provide local_clock_noinstr() x86/tsc: Provide sched_clock_noinstr() clocksource: hyper-v: Provide noinstr sched_clock() clocksource: hyper-v: Adjust hv_read_tsc_page_tsc() to avoid special casing U64_MAX x86/vdso: Fix gettimeofday masking math64: Always inline u128 version of mul_u64_u64_shr() s390/time: Provide sched_clock_noinstr() loongarch: Provide noinstr sched_clock_read() ...
2023-06-27Merge tag 'x86_mtrr_for_v6.5' of ↵Linus Torvalds1-0/+54
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 mtrr updates from Borislav Petkov: "A serious scrubbing of the MTRR code including adding a new map mechanism in order to look up the memory type of a region easily. Also address memory range lookup issues like returning an invalid memory type. Furthermore, this handles the decoupling of PAT from MTRR more naturally. All work by Juergen Gross" * tag 'x86_mtrr_for_v6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/xen: Set default memory type for PV guests to WB x86/mtrr: Unify debugging printing x86/mtrr: Remove unused code x86/mm: Only check uniform after calling mtrr_type_lookup() x86/mtrr: Don't let mtrr_type_lookup() return MTRR_TYPE_INVALID x86/mtrr: Use new cache_map in mtrr_type_lookup() x86/mtrr: Add mtrr=debug command line option x86/mtrr: Construct a memory map with cache modes x86/mtrr: Add get_effective_type() service function x86/mtrr: Allocate mtrr_value array dynamically x86/mtrr: Move 32-bit code from mtrr.c to legacy.c x86/mtrr: Have only one set_mtrr() variant x86/mtrr: Replace vendor tests in MTRR code x86/xen: Set MTRR state when running as Xen PV initial domain x86/hyperv: Set MTRR state when running as SEV-SNP Hyper-V guest x86/mtrr: Support setting MTRR state for software defined MTRRs x86/mtrr: Replace size_or_mask and size_and_mask with a much easier concept x86/mtrr: Remove physical address size calculation
2023-06-26x86: xen: add missing prototypesArnd Bergmann4-1/+9
These function are all called from assembler files, or from inline assembler, so there is no immediate need for a prototype in a header, but if -Wmissing-prototypes is enabled, the compiler warns about them: arch/x86/xen/efi.c:130:13: error: no previous prototype for 'xen_efi_init' [-Werror=missing-prototypes] arch/x86/platform/pvh/enlighten.c:120:13: error: no previous prototype for 'xen_prepare_pvh' [-Werror=missing-prototypes] arch/x86/xen/enlighten_pv.c:1233:34: error: no previous prototype for 'xen_start_kernel' [-Werror=missing-prototypes] arch/x86/xen/irq.c:22:14: error: no previous prototype for 'xen_force_evtchn_callback' [-Werror=missing-prototypes] arch/x86/entry/common.c:302:24: error: no previous prototype for 'xen_pv_evtchn_do_upcall' [-Werror=missing-prototypes] Declare all of them in an appropriate header file to avoid the warnings. For consistency, also move the asm_cpu_bringup_and_idle() declaration out of smp_pv.c. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lore.kernel.org/r/20230614073501.10101-3-jgross@suse.com Signed-off-by: Juergen Gross <jgross@suse.com>
2023-06-26x86/xen: add prototypes for paravirt mmu functionsJuergen Gross1-0/+16
The paravirt MMU functions called via the PV_CALLEE_SAVE_REGS_THUNK() macro can't be defined to be static, as the macro is generating a function via asm() statement calling the paravirt MMU function. In order to avoid warnings when specifying "-Wmissing-prototypes" for the build, add local prototypes (there should never be any external caller of those functions). Reported-by: Arnd Bergmann <arnd@kernel.org> Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lore.kernel.org/r/20230614073501.10101-2-jgross@suse.com Signed-off-by: Juergen Gross <jgross@suse.com>
2023-06-26iscsi_ibft: Fix finding the iBFT under Xen Dom 0Ross Lagerwall1-9/+19
To facilitate diskless iSCSI boot, the firmware can place a table of configuration details in memory called the iBFT. The presence of this table is not specified, nor is the precise location (and it's not in the E820) so the kernel has to search for a magic marker to find it. When running under Xen, Dom 0 does not have access to the entire host's memory, only certain regions which are identity-mapped which means that the pseudo-physical address in Dom0 == real host physical address. Add the iBFT search bounds as a reserved region which causes it to be identity-mapped in xen_set_identity_and_remap_chunk() which allows Dom0 access to the specific physical memory to correctly search for the iBFT magic marker (and later access the full table). This necessitates moving the call to reserve_ibft_region() somewhat later so that it is called after e820__memory_setup() which is when the Xen identity mapping adjustments are applied. The precise location of the call is not too important so I've put it alongside dmi_setup() which does similar scanning of memory for configuration tables. Finally in the iBFT find code, instead of using isa_bus_to_virt() which doesn't do the right thing under Xen, use early_memremap() like the dmi_setup() code does. The result of these changes is that it is possible to boot a diskless Xen + Dom0 running off an iSCSI disk whereas previously it would fail to find the iBFT and consequently, the iSCSI root disk. Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com> Reviewed-by: Juergen Gross <jgross@suse.com> Acked-by: Konrad Rzeszutek Wilk <konrad@darnok.org> Acked-by: Dave Hansen <dave.hansen@linux.intel.com> # for x86 Link: https://lore.kernel.org/r/20230605102840.1521549-1-ross.lagerwall@citrix.com Signed-off-by: Juergen Gross <jgross@suse.com>
2023-06-26xen: xen_debug_interrupt prototype to global headerArnd Bergmann1-2/+0
The xen_debug_interrupt() function is only called on x86, which has a prototype in an architecture specific header, but the definition also exists on others, where the lack of a prototype causes a W=1 warning: drivers/xen/events/events_2l.c:264:13: error: no previous prototype for 'xen_debug_interrupt' [-Werror=missing-prototypes] Move the prototype into a global header instead to avoid this warning. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Link: https://lore.kernel.org/r/20230517124525.929201-1-arnd@kernel.org Signed-off-by: Juergen Gross <jgross@suse.com>
2023-06-16x86/xen: Set default memory type for PV guests to WBJuergen Gross1-0/+2
When running as an unprivileged PV guest under Xen (not dom0), the default MTRR memory type should be write-back. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lore.kernel.org/r/20230615123959.12298-1-jgross@suse.com
2023-06-05x86/tsc: Provide sched_clock_noinstr()Peter Zijlstra1-2/+1
With the intent to provide local_clock_noinstr(), a variant of local_clock() that's safe to be called from noinstr code (with the assumption that any such code will already be non-preemptible), prepare for things by providing a noinstr sched_clock_noinstr() function. Specifically, preempt_enable_*() calls out to schedule(), which upsets noinstr validation efforts. vmlinux.o: warning: objtool: native_sched_clock+0x96: call to preempt_schedule_notrace_thunk() leaves .noinstr.text section vmlinux.o: warning: objtool: kvm_clock_read+0x22: call to preempt_schedule_notrace_thunk() leaves .noinstr.text section Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Michael Kelley <mikelley@microsoft.com> # Hyper-V Link: https://lore.kernel.org/r/20230519102715.910937674@infradead.org
2023-06-01x86/xen: Set MTRR state when running as Xen PV initial domainJuergen Gross1-0/+52
When running as Xen PV initial domain (aka dom0), MTRRs are disabled by the hypervisor, but the system should nevertheless use correct cache memory types. This has always kind of worked, as disabled MTRRs resulted in disabled PAT, too, so that the kernel avoided code paths resulting in inconsistencies. This bypassed all of the sanity checks the kernel is doing with enabled MTRRs in order to avoid memory mappings with conflicting memory types. This has been changed recently, leading to PAT being accepted to be enabled, while MTRRs stayed disabled. The result is that mtrr_type_lookup() no longer is accepting all memory type requests, but started to return WB even if UC- was requested. This led to driver failures during initialization of some devices. In reality MTRRs are still in effect, but they are under complete control of the Xen hypervisor. It is possible, however, to retrieve the MTRR settings from the hypervisor. In order to fix those problems, overwrite the MTRR state via mtrr_overwrite_state() with the MTRR data from the hypervisor, if the system is running as a Xen dom0. Fixes: 72cbc8f04fe2 ("x86/PAT: Have pat_enabled() properly reflect state when running on Xen") Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Tested-by: Michael Kelley <mikelley@microsoft.com> Link: https://lore.kernel.org/r/20230502120931.20719-6-jgross@suse.com Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
2023-05-15x86/smpboot: Enable split CPU startupThomas Gleixner1-2/+2
The x86 CPU bringup state currently does AP wake-up, wait for AP to respond and then release it for full bringup. It is safe to be split into a wake-up and and a separate wait+release state. Provide the required functions and enable the split CPU bringup, which prepares for parallel bringup, where the bringup of the non-boot CPUs takes two iterations: One to prepare and wake all APs and the second to wait and release them. Depending on timing this can eliminate the wait time completely. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name> Tested-by: Helge Deller <deller@gmx.de> # parisc Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com> # Steam Deck Link: https://lore.kernel.org/r/20230512205257.133453992@linutronix.de
2023-05-15x86/smpboot: Switch to hotplug core state synchronizationThomas Gleixner2-26/+29
The new AP state tracking and synchronization mechanism in the CPU hotplug core code allows to remove quite some x86 specific code: 1) The AP alive synchronization based on cpumasks 2) The decision whether an AP can be brought up again Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name> Tested-by: Helge Deller <deller@gmx.de> # parisc Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com> # Steam Deck Link: https://lore.kernel.org/r/20230512205256.529657366@linutronix.de
2023-05-15x86/xen/hvm: Get rid of DEAD_FROZEN handlingThomas Gleixner1-6/+5
No point in this conditional voodoo. Un-initializing the lock mechanism is safe to be called unconditionally even if it was already invoked when the CPU died. Remove the invocation of xen_smp_intr_free() as that has been already cleaned up in xen_cpu_dead_hvm(). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name> Tested-by: Helge Deller <deller@gmx.de> # parisc Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com> # Steam Deck Link: https://lore.kernel.org/r/20230512205256.423407127@linutronix.de
2023-05-15x86/xen/smp_pv: Remove wait for CPU onlineThomas Gleixner1-5/+5
Now that the core code drops sparse_irq_lock after the idle thread synchronized, it's pointless to wait for the AP to mark itself online. Whether the control CPU runs in a wait loop or sleeps in the core code waiting for the online operation to complete makes no difference. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name> Tested-by: Helge Deller <deller@gmx.de> # parisc Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com> # Steam Deck Link: https://lore.kernel.org/r/20230512205256.369512093@linutronix.de
2023-05-15x86/smpboot: Move synchronization masks to SMP boot codeThomas Gleixner1-3/+0
The usage is in smpboot.c and not in the CPU initialization code. The XEN_PV usage of cpu_callout_mask is obsolete as cpu_init() not longer waits and cacheinfo has its own CPU mask now, so cpu_callout_mask can be made static too. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name> Tested-by: Helge Deller <deller@gmx.de> # parisc Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com> # Steam Deck Link: https://lore.kernel.org/r/20230512205256.091511483@linutronix.de
2023-04-29Merge tag 'objtool-core-2023-04-27' of ↵Linus Torvalds2-4/+4
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull objtool updates from Ingo Molnar: - Mark arch_cpu_idle_dead() __noreturn, make all architectures & drivers that did this inconsistently follow this new, common convention, and fix all the fallout that objtool can now detect statically - Fix/improve the ORC unwinder becoming unreliable due to UNWIND_HINT_EMPTY ambiguity, split it into UNWIND_HINT_END_OF_STACK and UNWIND_HINT_UNDEFINED to resolve it - Fix noinstr violations in the KCSAN code and the lkdtm/stackleak code - Generate ORC data for __pfx code - Add more __noreturn annotations to various kernel startup/shutdown and panic functions - Misc improvements & fixes * tag 'objtool-core-2023-04-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (52 commits) x86/hyperv: Mark hv_ghcb_terminate() as noreturn scsi: message: fusion: Mark mpt_halt_firmware() __noreturn x86/cpu: Mark {hlt,resume}_play_dead() __noreturn btrfs: Mark btrfs_assertfail() __noreturn objtool: Include weak functions in global_noreturns check cpu: Mark nmi_panic_self_stop() __noreturn cpu: Mark panic_smp_self_stop() __noreturn arm64/cpu: Mark cpu_park_loop() and friends __noreturn x86/head: Mark *_start_kernel() __noreturn init: Mark start_kernel() __noreturn init: Mark [arch_call_]rest_init() __noreturn objtool: Generate ORC data for __pfx code x86/linkage: Fix padding for typed functions objtool: Separate prefix code from stack validation code objtool: Remove superfluous dead_end_function() check objtool: Add symbol iteration helpers objtool: Add WARN_INSN() scripts/objdump-func: Support multiple functions context_tracking: Fix KCSAN noinstr violation objtool: Add stackleak instrumentation to uaccess safe list ...
2023-04-25Merge tag 'x86-apic-2023-04-24' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 APIC updates from Thomas Gleixner: - Fix the incorrect handling of atomic offset updates in reserve_eilvt_offset() The check for the return value of atomic_cmpxchg() is not compared against the old value, it is compared against the new value, which makes it two round on success. Convert it to atomic_try_cmpxchg() which does the right thing. - Handle IO/APIC less systems correctly When IO/APIC is not advertised by ACPI then the computation of the lower bound for dynamically allocated interrupts like MSI goes wrong. This lower bound is used to exclude the IO/APIC legacy GSI space as that must stay reserved for the legacy interrupts. In case that the system, e.g. VM, does not advertise an IO/APIC the lower bound stays at 0. 0 is an invalid interrupt number except for the legacy timer interrupt on x86. The return value is unchecked in the core code, so it ends up to allocate interrupt number 0 which is subsequently considered to be invalid by the caller, e.g. the MSI allocation code. A similar problem was already cured for device tree based systems years ago, but that missed - or did not envision - the zero IO/APIC case. Consolidate the zero check and return the provided "from" argument to the core code call site, which is guaranteed to be greater than 0. - Simplify the X2APIC cluster CPU mask logic for CPU hotplug Per cluster CPU masks are required for X2APIC in cluster mode to determine the correct cluster for a target CPU when calculating the destination for IPIs These masks are established when CPUs are borught up. The first CPU in a cluster must allocate a new cluster CPU mask. As this happens during the early startup of a CPU, where memory allocations cannot be done, the mask has to be allocated by the control CPU. The current implementation allocates a clustermask just in case and if the to be brought up CPU is the first in a cluster the CPU takes over this allocation from a global pointer. This works nicely in the fully serialized CPU bringup scenario which is used today, but would fail completely for parallel bringup of CPUs. The cluster association of a CPU can be computed from the APIC ID which is enumerated by ACPI/MADT. So the cluster CPU masks can be preallocated and associated upfront and the upcoming CPUs just need to set their corresponding bit. Aside of preparing for parallel bringup this is a valuable simplification on its own. - Remove global variables which control the early startup of secondary CPUs on 64-bit The only information which is needed by a starting CPU is the Linux CPU number. The CPU number allows it to retrieve the rest of the required data from already existing per CPU storage. So instead of initial_stack, early_gdt_desciptor and initial_gs provide a new variable smpboot_control which contains the Linux CPU number for now. The starting CPU can retrieve and compute all required information for startup from there. Aside of being a cleanup, this is also preparing for parallel CPU bringup, where starting CPUs will look up their Linux CPU number via the APIC ID, when smpboot_control has the corresponding control bit set. - Make cc_vendor globally accesible Subsequent parallel bringup changes require access to cc_vendor because confidental computing platforms need special treatment in the early startup phase vs. CPUID and APCI ID readouts. The change makes cc_vendor global and provides stub accessors in case that CONFIG_ARCH_HAS_CC_PLATFORM is not set. This was merged from the x86/cc branch in anticipation of further parallel bringup commits which require access to cc_vendor. Due to late discoveries of fundamental issue with those patches these commits never happened. The merge commit is unfortunately in the middle of the APIC commits so unraveling it would have required a rebase or revert. As the parallel bringup seems to be well on its way for 6.5 this would be just pointless churn. As the commit does not contain any functional change it's not a risk to keep it. * tag 'x86-apic-2023-04-24' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/ioapic: Don't return 0 from arch_dynirq_lower_bound() x86/apic: Fix atomic update of offset in reserve_eilvt_offset() x86/coco: Export cc_vendor x86/smpboot: Reference count on smpboot_setup_warm_reset_vector() x86/smpboot: Remove initial_gs x86/smpboot: Remove early_gdt_descr on 64-bit x86/smpboot: Remove initial_stack on 64-bit x86/apic/x2apic: Allow CPU cluster_mask to be populated in parallel
2023-04-25Merge tag 'x86_paravirt_for_v6.4_rc1' of ↵Linus Torvalds1-10/+2
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 paravirt updates from Borislav Petkov: - Convert a couple of paravirt callbacks to asm to prevent '-fzero-call-used-regs' builds from zeroing live registers because paravirt hides the CALLs from the compiler so latter doesn't know there's a CALL in the first place - Merge two paravirt callbacks into one, as their functionality is identical * tag 'x86_paravirt_for_v6.4_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/paravirt: Convert simple paravirt functions to asm x86/paravirt: Merge activate_mm() and dup_mmap() callbacks
2023-03-24Merge tag 'for-linus-6.3-rc4-tag' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen fixes from Juergen Gross: - fix build warning - avoid concurrent accesses to the Xen PV console ring page * tag 'for-linus-6.3-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: x86/PVH: avoid 32-bit build warning when obtaining VGA console info hvc/xen: prevent concurrent accesses to the shared ring
2023-03-24x86,objtool: Split UNWIND_HINT_EMPTY in twoJosh Poimboeuf2-4/+4
Mark reported that the ORC unwinder incorrectly marks an unwind as reliable when the unwind terminates prematurely in the dark corners of return_to_handler() due to lack of information about the next frame. The problem is UNWIND_HINT_EMPTY is used in two different situations: 1) The end of the kernel stack unwind before hitting user entry, boot code, or fork entry 2) A blind spot in ORC coverage where the unwinder has to bail due to lack of information about the next frame The ORC unwinder has no way to tell the difference between the two. When it encounters an undefined stack state with 'end=1', it blindly marks the stack reliable, which can break the livepatch consistency model. Fix it by splitting UNWIND_HINT_EMPTY into UNWIND_HINT_UNDEFINED and UNWIND_HINT_END_OF_STACK. Reported-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/fd6212c8b450d3564b855e1cb48404d6277b4d9f.1677683419.git.jpoimboe@kernel.org
2023-03-22x86/PVH: avoid 32-bit build warning when obtaining VGA console infoJan Beulich1-1/+1
In the commit referenced below I failed to pay attention to this code also being buildable as 32-bit. Adjust the type of "ret" - there's no real need for it to be wider than 32 bits. Fixes: 934ef33ee75c ("x86/PVH: obtain VGA console info in Dom0") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/2d2193ff-670b-0a27-e12d-2c5c4c121c79@suse.com Signed-off-by: Juergen Gross <jgross@suse.com>
2023-03-21x86/smpboot: Remove initial_stack on 64-bitBrian Gerst1-1/+1
In order to facilitate parallel startup, start to eliminate some of the global variables passing information to CPUs in the startup path. However, start by introducing one more: smpboot_control. For now this merely holds the CPU# of the CPU which is coming up. Each CPU can then find its own per-cpu data, and everything else it needs can be found from there, allowing the other global variables to be removed. First to be removed is initial_stack. Each CPU can load %rsp from its current_task->thread.sp instead. That is already set up with the correct idle thread for APs. Set up the .sp field in INIT_THREAD on x86 so that the BSP also finds a suitable stack pointer in the static per-cpu data when coming up on first boot. On resume from S3, the CPU needs a temporary stack because its idle task is already active. Instead of setting initial_stack, the sleep code can simply set its own current->thread.sp to point to the temporary stack. Nobody else cares about ->thread.sp for a thread which is currently on a CPU, because the true value is actually in the %rsp register. Which is restored with the rest of the CPU context in do_suspend_lowlevel(). Signed-off-by: Brian Gerst <brgerst@gmail.com> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Usama Arif <usama.arif@bytedance.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Usama Arif <usama.arif@bytedance.com> Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com> Reviewed-by: David Woodhouse <dwmw@amazon.co.uk> Link: https://lore.kernel.org/r/20230316222109.1940300-7-usama.arif@bytedance.com
2023-03-17Merge tag 'for-linus-6.3-rc3-tag' of ↵Linus Torvalds6-13/+24
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen fixes from Juergen Gross: - cleanup for xen time handling - enable the VGA console in a Xen PVH dom0 - cleanup in the xenfs driver * tag 'for-linus-6.3-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen: remove unnecessary (void*) conversions x86/PVH: obtain VGA console info in Dom0 x86/xen/time: cleanup xen_tsc_safe_clocksource xen: update arch/x86/include/asm/xen/cpuid.h
2023-03-14x86/PVH: obtain VGA console info in Dom0Jan Beulich5-8/+22
A new platform-op was added to Xen to allow obtaining the same VGA console information PV Dom0 is handed. Invoke the new function and have the output data processed by xen_init_vga(). Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/8f315e92-7bda-c124-71cc-478ab9c5e610@suse.com Signed-off-by: Juergen Gross <jgross@suse.com>
2023-03-06x86/paravirt: Merge activate_mm() and dup_mmap() callbacksJuergen Gross1-10/+2
The two paravirt callbacks .mmu.activate_mm() and .mmu.dup_mmap() are sharing the same implementations in all cases: for Xen PV guests they are pinning the PGD of the new mm_struct, and for all other cases they are a NOP. In the end, both callbacks are meant to register an address space with the underlying hypervisor, so there needs to be only a single callback for that purpose. So merge them to a common callback .mmu.enter_mmap() (in contrast to the corresponding already existing .mmu.exit_mmap()). As the first parameter of the old callbacks isn't used, drop it from the replacement one. [ bp: Remove last occurrence of paravirt_activate_mm() in asm/mmu_context.h ] Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu> Link: https://lore.kernel.org/r/20230207075902.7539-1-jgross@suse.com
2023-02-23x86/xen/time: cleanup xen_tsc_safe_clocksourceKrister Johansen1-5/+2
Modifies xen_tsc_safe_clocksource() to use newly defined constants from arch/x86/include/asm/xen/cpuid.h. This replaces a numeric value with XEN_CPUID_TSC_MODE_NEVER_EMULATE, and deletes a comment that is now self explanatory. There should be no change in the function's behavior. Signed-off-by: Krister Johansen <kjlx@templeofstupid.com> Reviewed-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/a69ca370fecf85d312d2db633d9438ace2af6e5b.1677038165.git.kjlx@templeofstupid.com Signed-off-by: Juergen Gross <jgross@suse.com>
2023-02-22Merge tag 'for-linus-6.3-rc1-tag' of ↵Linus Torvalds5-18/+50
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen updates from Juergen Gross: - help deprecate the /proc/xen files by making the related information available via sysfs - mark the Xen variants of play_dead "noreturn" - support a shared Xen platform interrupt - several small cleanups and fixes * tag 'for-linus-6.3-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen: sysfs: make kobj_type structure constant x86/Xen: drop leftover VM-assist uses xen: Replace one-element array with flexible-array member xen/grant-dma-iommu: Implement a dummy probe_device() callback xen/pvcalls-back: fix permanently masked event channel xen: Allow platform PCI interrupt to be shared x86/xen/time: prefer tsc as clocksource when it is invariant x86/xen: mark xen_pv_play_dead() as __noreturn x86/xen: don't let xen_pv_play_dead() return drivers/xen/hypervisor: Expose Xen SIF flags to userspace
2023-02-22Merge tag 'x86_cpu_for_v6.3_rc1' of ↵Linus Torvalds1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cpuid updates from Borislav Petkov: - Cache the AMD debug registers in per-CPU variables to avoid MSR writes where possible, when supporting a debug registers swap feature for SEV-ES guests - Add support for AMD's version of eIBRS called Automatic IBRS which is a set-and-forget control of indirect branch restriction speculation resources on privilege change - Add support for a new x86 instruction - LKGS - Load kernel GS which is part of the FRED infrastructure - Reset SPEC_CTRL upon init to accomodate use cases like kexec which rediscover - Other smaller fixes and cleanups * tag 'x86_cpu_for_v6.3_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/amd: Cache debug register values in percpu variables KVM: x86: Propagate the AMD Automatic IBRS feature to the guest x86/cpu: Support AMD Automatic IBRS x86/cpu, kvm: Add the SMM_CTL MSR not present feature x86/cpu, kvm: Add the Null Selector Clears Base feature x86/cpu, kvm: Move X86_FEATURE_LFENCE_RDTSC to its native leaf x86/cpu, kvm: Add the NO_NESTED_DATA_BP feature KVM: x86: Move open-coded CPUID leaf 0x80000021 EAX bit propagation code x86/cpu, kvm: Add support for CPUID_80000021_EAX x86/gsseg: Add the new <asm/gsseg.h> header to <asm/asm-prototypes.h> x86/gsseg: Use the LKGS instruction if available for load_gs_index() x86/gsseg: Move load_gs_index() to its own new header file x86/gsseg: Make asm_load_gs_index() take an u16 x86/opcode: Add the LKGS instruction to x86-opcode-map x86/cpufeature: Add the CPU feature bit for LKGS x86/bugs: Reset speculation control settings on init x86/cpu: Remove redundant extern x86_read_arch_cap_msr()
2023-02-18x86/Xen: drop leftover VM-assist usesJan Beulich1-4/+0
Both the 4Gb-segments and the PAE-extended-CR3 one are applicable to 32-bit guests only. The PAE-extended-CR3 use, furthermore, was redundant with the PAE_MODE ELF note anyway. Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/215515af-cfb9-3237-03ba-3312e3fa0d34@suse.com Signed-off-by: Juergen Gross <jgross@suse.com>
2023-02-13x86/xen/time: prefer tsc as clocksource when it is invariantKrister Johansen1-1/+37
Kvm elects to use tsc instead of kvm-clock when it can detect that the TSC is invariant. (As of commit 7539b174aef4 ("x86: kvmguest: use TSC clocksource if invariant TSC is exposed")). Notable cloud vendors[1] and performance engineers[2] recommend that Xen users preferentially select tsc over xen-clocksource due the performance penalty incurred by the latter. These articles are persuasive and tailored to specific use cases. In order to understand the tradeoffs around this choice more fully, this author had to reference the documented[3] complexities around the Xen configuration, as well as the kernel's clocksource selection algorithm. Many users may not attempt this to correctly configure the right clock source in their guest. The approach taken in the kvm-clock module spares users this confusion, where possible. Both the Intel SDM[4] and the Xen tsc documentation explain that marking a tsc as invariant means that it should be considered stable by the OS and is elibile to be used as a wall clock source. In order to obtain better out-of-the-box performance, and reduce the need for user tuning, follow kvm's approach and decrease the xen clock rating so that tsc is preferable, if it is invariant, stable, and the tsc will never be emulated. [1] https://aws.amazon.com/premiumsupport/knowledge-center/manage-ec2-linux-clock-source/ [2] https://www.brendangregg.com/blog/2021-09-26/the-speed-of-time.html [3] https://xenbits.xen.org/docs/unstable/man/xen-tscmode.7.html [4] Intel 64 and IA-32 Architectures Sofware Developer's Manual Volume 3b: System Programming Guide, Part 2, Section 17.17.1, Invariant TSC Signed-off-by: Krister Johansen <kjlx@templeofstupid.com> Code-reviewed-by: David Reaver <me@davidreaver.com> Reviewed-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/20221216162118.GB2633@templeofstupid.com Signed-off-by: Juergen Gross <jgross@suse.com>
2023-02-13x86/xen: mark xen_pv_play_dead() as __noreturnJuergen Gross2-3/+3
Mark xen_pv_play_dead() and related to that xen_cpu_bringup_again() as "__noreturn". Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20221125063248.30256-3-jgross@suse.com Signed-off-by: Juergen Gross <jgross@suse.com>
2023-02-13x86/xen: don't let xen_pv_play_dead() returnJuergen Gross3-11/+11
A function called via the paravirt play_dead() hook should not return to the caller. xen_pv_play_dead() has a problem in this regard, as it currently will return in case an offlined cpu is brought to life again. This can be changed only by doing basically a longjmp() to cpu_bringup_and_idle(), as the hypercall for bringing down the cpu will just return when the cpu is coming up again. Just re-initializing the cpu isn't possible, as the Xen hypervisor will deny that operation. So introduce xen_cpu_bringup_again() resetting the stack and calling cpu_bringup_and_idle(), which can be called after HYPERVISOR_vcpu_op() in xen_pv_play_dead(). Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20221125063248.30256-2-jgross@suse.com Signed-off-by: Juergen Gross <jgross@suse.com>
2023-01-31sched/clock/x86: Mark sched_clock() noinstrPeter Zijlstra1-2/+10
In order to use sched_clock() from noinstr code, mark it and all it's implenentations noinstr. The whole pvclock thing (used by KVM/Xen) is a bit of a pain, since it calls out to watchdogs, create a pvclock_clocksource_read_nowd() variant doesn't do that and can be noinstr. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20230126151323.702003578@infradead.org
2023-01-31Merge tag 'v6.2-rc6' into sched/core, to pick up fixesIngo Molnar1-5/+0
Pick up fixes before merging another batch of cpuidle updates. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2023-01-13cpuidle, xenpv: Make more PARAVIRT_XXL noinstr cleanPeter Zijlstra2-2/+2
objtool found a few cases where this code called out into instrumented code: vmlinux.o: warning: objtool: acpi_idle_enter_s2idle+0xde: call to wbinvd() leaves .noinstr.text section vmlinux.o: warning: objtool: default_idle+0x4: call to arch_safe_halt() leaves .noinstr.text section vmlinux.o: warning: objtool: xen_safe_halt+0xa: call to HYPERVISOR_sched_op.constprop.0() leaves .noinstr.text section Solve this by: - marking arch_safe_halt(), wbinvd(), native_wbinvd() and HYPERVISOR_sched_op() as __always_inline(). - Explicitly uninlining xen_safe_halt() and pv_native_wbinvd() [they were already uninlined by the compiler on use as function pointers] and annotating them as 'noinstr'. - Annotating pv_native_safe_halt() as 'noinstr'. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Tested-by: Tony Lindgren <tony@atomide.com> Tested-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu> Reviewed-by: Juergen Gross <jgross@suse.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/20230112195541.171918174@infradead.org
2023-01-13x86/gsseg: Use the LKGS instruction if available for load_gs_index()H. Peter Anvin (Intel)1-0/+1
The LKGS instruction atomically loads a segment descriptor into the %gs descriptor registers, *except* that %gs.base is unchanged, and the base is instead loaded into MSR_IA32_KERNEL_GS_BASE, which is exactly what we want this function to do. Signed-off-by: H. Peter Anvin (Intel) <hpa@zytor.com> Signed-off-by: Xin Li <xin3.li@intel.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20230112072032.35626-6-xin3.li@intel.com Cc: Andy Lutomirski <luto@kernel.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org>
2023-01-13Merge tag 'for-linus-6.2-rc4-tag' of ↵Linus Torvalds1-5/+0
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen fixes from Juergen Gross: - two cleanup patches - a fix of a memory leak in the Xen pvfront driver - a fix of a locking issue in the Xen hypervisor console driver * tag 'for-linus-6.2-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen/pvcalls: free active map buffer on pvcalls_front_free_map hvc/xen: lock console list traversal x86/xen: Remove the unused function p2m_index() xen: make remove callback of xen driver void returned
2023-01-09x86/xen: Remove the unused function p2m_index()Jiapeng Chong1-5/+0
The function p2m_index is defined in the p2m.c file, but not called elsewhere, so remove this unused function. arch/x86/xen/p2m.c:137:24: warning: unused function 'p2m_index'. Link: https://bugzilla.openanolis.cn/show_bug.cgi?id=3557 Reported-by: Abaci Robot <abaci@linux.alibaba.com> Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com> Reviewed-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/20230105090141.36248-1-jiapeng.chong@linux.alibaba.com Signed-off-by: Juergen Gross <jgross@suse.com>
2022-12-15Merge tag 'x86_core_for_v6.2' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 core updates from Borislav Petkov: - Add the call depth tracking mitigation for Retbleed which has been long in the making. It is a lighterweight software-only fix for Skylake-based cores where enabling IBRS is a big hammer and causes a significant performance impact. What it basically does is, it aligns all kernel functions to 16 bytes boundary and adds a 16-byte padding before the function, objtool collects all functions' locations and when the mitigation gets applied, it patches a call accounting thunk which is used to track the call depth of the stack at any time. When that call depth reaches a magical, microarchitecture-specific value for the Return Stack Buffer, the code stuffs that RSB and avoids its underflow which could otherwise lead to the Intel variant of Retbleed. This software-only solution brings a lot of the lost performance back, as benchmarks suggest: https://lore.kernel.org/all/20220915111039.092790446@infradead.org/ That page above also contains a lot more detailed explanation of the whole mechanism - Implement a new control flow integrity scheme called FineIBT which is based on the software kCFI implementation and uses hardware IBT support where present to annotate and track indirect branches using a hash to validate them - Other misc fixes and cleanups * tag 'x86_core_for_v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (80 commits) x86/paravirt: Use common macro for creating simple asm paravirt functions x86/paravirt: Remove clobber bitmask from .parainstructions x86/debug: Include percpu.h in debugreg.h to get DECLARE_PER_CPU() et al x86/cpufeatures: Move X86_FEATURE_CALL_DEPTH from bit 18 to bit 19 of word 11, to leave space for WIP X86_FEATURE_SGX_EDECCSSA bit x86/Kconfig: Enable kernel IBT by default x86,pm: Force out-of-line memcpy() objtool: Fix weak hole vs prefix symbol objtool: Optimize elf_dirty_reloc_sym() x86/cfi: Add boot time hash randomization x86/cfi: Boot time selection of CFI scheme x86/ibt: Implement FineIBT objtool: Add --cfi to generate the .cfi_sites section x86: Add prefix symbols for function padding objtool: Add option to generate prefix symbols objtool: Avoid O(bloody terrible) behaviour -- an ode to libelf objtool: Slice up elf_create_section_symbol() kallsyms: Revert "Take callthunks into account" x86: Unconfuse CONFIG_ and X86_FEATURE_ namespaces x86/retpoline: Fix crash printing warning x86/paravirt: Fix a !PARAVIRT build warning ...
2022-12-14Merge tag 'x86_boot_for_v6.2' of ↵Linus Torvalds1-0/+2
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 boot updates from Borislav Petkov: "A of early boot cleanups and fixes. - Do some spring cleaning to the compressed boot code by moving the EFI mixed-mode code to a separate compilation unit, the AMD memory encryption early code where it belongs and fixing up build dependencies. Make the deprecated EFI handover protocol optional with the goal of removing it at some point (Ard Biesheuvel) - Skip realmode init code on Xen PV guests as it is not needed there - Remove an old 32-bit PIC code compiler workaround" * tag 'x86_boot_for_v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/boot: Remove x86_32 PIC using %ebx workaround x86/boot: Skip realmode init code when running as Xen PV guest x86/efi: Make the deprecated EFI handover protocol optional x86/boot/compressed: Only build mem_encrypt.S if AMD_MEM_ENCRYPT=y x86/boot/compressed: Adhere to calling convention in get_sev_encryption_bit() x86/boot/compressed: Move startup32_check_sev_cbit() out of head_64.S x86/boot/compressed: Move startup32_check_sev_cbit() into .text x86/boot/compressed: Move startup32_load_idt() out of head_64.S x86/boot/compressed: Move startup32_load_idt() into .text section x86/boot/compressed: Pull global variable reference into startup32_load_idt() x86/boot/compressed: Avoid touching ECX in startup32_set_idt_entry() x86/boot/compressed: Simplify IDT/GDT preserve/restore in the EFI thunk x86/boot/compressed, efi: Merge multiple definitions of image_offset into one x86/boot/compressed: Move efi32_pe_entry() out of head_64.S x86/boot/compressed: Move efi32_entry out of head_64.S x86/boot/compressed: Move efi32_pe_entry into .text section x86/boot/compressed: Move bootargs parsing out of 32-bit startup code x86/boot/compressed: Move 32-bit entrypoint code into .text section x86/boot/compressed: Rename efi_thunk_64.S to efi-mixed.S
2022-12-13Merge tag 'random-6.2-rc1-for-linus' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/crng/random Pull random number generator updates from Jason Donenfeld: - Replace prandom_u32_max() and various open-coded variants of it, there is now a new family of functions that uses fast rejection sampling to choose properly uniformly random numbers within an interval: get_random_u32_below(ceil) - [0, ceil) get_random_u32_above(floor) - (floor, U32_MAX] get_random_u32_inclusive(floor, ceil) - [floor, ceil] Coccinelle was used to convert all current users of prandom_u32_max(), as well as many open-coded patterns, resulting in improvements throughout the tree. I'll have a "late" 6.1-rc1 pull for you that removes the now unused prandom_u32_max() function, just in case any other trees add a new use case of it that needs to converted. According to linux-next, there may be two trivial cases of prandom_u32_max() reintroductions that are fixable with a 's/.../.../'. So I'll have for you a final conversion patch doing that alongside the removal patch during the second week. This is a treewide change that touches many files throughout. - More consistent use of get_random_canary(). - Updates to comments, documentation, tests, headers, and simplification in configuration. - The arch_get_random*_early() abstraction was only used by arm64 and wasn't entirely useful, so this has been replaced by code that works in all relevant contexts. - The kernel will use and manage random seeds in non-volatile EFI variables, refreshing a variable with a fresh seed when the RNG is initialized. The RNG GUID namespace is then hidden from efivarfs to prevent accidental leakage. These changes are split into random.c infrastructure code used in the EFI subsystem, in this pull request, and related support inside of EFISTUB, in Ard's EFI tree. These are co-dependent for full functionality, but the order of merging doesn't matter. - Part of the infrastructure added for the EFI support is also used for an improvement to the way vsprintf initializes its siphash key, replacing an sleep loop wart. - The hardware RNG framework now always calls its correct random.c input function, add_hwgenerator_randomness(), rather than sometimes going through helpers better suited for other cases. - The add_latent_entropy() function has long been called from the fork handler, but is a no-op when the latent entropy gcc plugin isn't used, which is fine for the purposes of latent entropy. But it was missing out on the cycle counter that was also being mixed in beside the latent entropy variable. So now, if the latent entropy gcc plugin isn't enabled, add_latent_entropy() will expand to a call to add_device_randomness(NULL, 0), which adds a cycle counter, without the absent latent entropy variable. - The RNG is now reseeded from a delayed worker, rather than on demand when used. Always running from a worker allows it to make use of the CPU RNG on platforms like S390x, whose instructions are too slow to do so from interrupts. It also has the effect of adding in new inputs more frequently with more regularity, amounting to a long term transcript of random values. Plus, it helps a bit with the upcoming vDSO implementation (which isn't yet ready for 6.2). - The jitter entropy algorithm now tries to execute on many different CPUs, round-robining, in hopes of hitting even more memory latencies and other unpredictable effects. It also will mix in a cycle counter when the entropy timer fires, in addition to being mixed in from the main loop, to account more explicitly for fluctuations in that timer firing. And the state it touches is now kept within the same cache line, so that it's assured that the different execution contexts will cause latencies. * tag 'random-6.2-rc1-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/crng/random: (23 commits) random: include <linux/once.h> in the right header random: align entropy_timer_state to cache line random: mix in cycle counter when jitter timer fires random: spread out jitter callback to different CPUs random: remove extraneous period and add a missing one in comments efi: random: refresh non-volatile random seed when RNG is initialized vsprintf: initialize siphash key using notifier random: add back async readiness notifier random: reseed in delayed work rather than on-demand random: always mix cycle counter in add_latent_entropy() hw_random: use add_hwgenerator_randomness() for early entropy random: modernize documentation comment on get_random_bytes() random: adjust comment to account for removed function random: remove early archrandom abstraction random: use random.trust_{bootloader,cpu} command line option only stackprotector: actually use get_random_canary() stackprotector: move get_random_canary() into stackprotector.h treewide: use get_random_u32_inclusive() when possible treewide: use get_random_u32_{above,below}() instead of manual loop treewide: use get_random_u32_below() instead of deprecated function ...