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2022-08-12x86/xen: Add support for HVMOP_set_evtchn_upcall_vectorJane Malalane
Implement support for the HVMOP_set_evtchn_upcall_vector hypercall in order to set the per-vCPU event channel vector callback on Linux and use it in preference of HVM_PARAM_CALLBACK_IRQ. If the per-VCPU vector setup is successful on BSP, use this method for the APs. If not, fallback to the global vector-type callback. Also register callback_irq at per-vCPU event channel setup to trick toolstack to think the domain is enlightened. Suggested-by: "Roger Pau Monné" <roger.pau@citrix.com> Signed-off-by: Jane Malalane <jane.malalane@citrix.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lore.kernel.org/r/20220729070416.23306-1-jane.malalane@citrix.com Signed-off-by: Juergen Gross <jgross@suse.com>
2022-08-01xen: don't require virtio with grants for non-PV guestsJuergen Gross
Commit fa1f57421e0b ("xen/virtio: Enable restricted memory access using Xen grant mappings") introduced a new requirement for using virtio devices: the backend now needs to support the VIRTIO_F_ACCESS_PLATFORM feature. This is an undue requirement for non-PV guests, as those can be operated with existing backends without any problem, as long as those backends are running in dom0. Per default allow virtio devices without grant support for non-PV guests. On Arm require VIRTIO_F_ACCESS_PLATFORM for devices having been listed in the device tree to use grants. Add a new config item to always force use of grants for virtio. Fixes: fa1f57421e0b ("xen/virtio: Enable restricted memory access using Xen grant mappings") Reported-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> Tested-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> # Arm64 guest using Xen Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Link: https://lore.kernel.org/r/20220622063838.8854-4-jgross@suse.com Signed-off-by: Juergen Gross <jgross@suse.com>
2022-07-11Merge tag 'x86_bugs_retbleed' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 retbleed fixes from Borislav Petkov: "Just when you thought that all the speculation bugs were addressed and solved and the nightmare is complete, here's the next one: speculating after RET instructions and leaking privileged information using the now pretty much classical covert channels. It is called RETBleed and the mitigation effort and controlling functionality has been modelled similar to what already existing mitigations provide" * tag 'x86_bugs_retbleed' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (54 commits) x86/speculation: Disable RRSBA behavior x86/kexec: Disable RET on kexec x86/bugs: Do not enable IBPB-on-entry when IBPB is not supported x86/entry: Move PUSH_AND_CLEAR_REGS() back into error_entry x86/bugs: Add Cannon lake to RETBleed affected CPU list x86/retbleed: Add fine grained Kconfig knobs x86/cpu/amd: Enumerate BTC_NO x86/common: Stamp out the stepping madness KVM: VMX: Prevent RSB underflow before vmenter x86/speculation: Fill RSB on vmexit for IBRS KVM: VMX: Fix IBRS handling after vmexit KVM: VMX: Prevent guest RSB poisoning attacks with eIBRS KVM: VMX: Convert launched argument to flags KVM: VMX: Flatten __vmx_vcpu_run() objtool: Re-add UNWIND_HINT_{SAVE_RESTORE} x86/speculation: Remove x86_spec_ctrl_mask x86/speculation: Use cached host SPEC_CTRL value for guest entry/exit x86/speculation: Fix SPEC_CTRL write on SMT state change x86/speculation: Fix firmware entry SPEC_CTRL handling x86/speculation: Fix RSB filling with CONFIG_RETPOLINE=n ...
2022-07-01x86/xen: Use clear_bss() for Xen PV guestsJuergen Gross
Instead of clearing the bss area in assembly code, use the clear_bss() function. This requires to pass the start_info address as parameter to xen_start_kernel() in order to avoid the xen_start_info being zeroed again. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lore.kernel.org/r/20220630071441.28576-2-jgross@suse.com
2022-06-27objtool: Add entry UNRET validationPeter Zijlstra
Since entry asm is tricky, add a validation pass that ensures the retbleed mitigation has been done before the first actual RET instruction. Entry points are those that either have UNWIND_HINT_ENTRY, which acts as UNWIND_HINT_EMPTY but marks the instruction as an entry point, or those that have UWIND_HINT_IRET_REGS at +0. This is basically a variant of validate_branch() that is intra-function and it will simply follow all branches from marked entry points and ensures that all paths lead to ANNOTATE_UNRET_END. If a path hits RET or an indirection the path is a fail and will be reported. There are 3 ANNOTATE_UNRET_END instances: - UNTRAIN_RET itself - exception from-kernel; this path doesn't need UNTRAIN_RET - all early exceptions; these also don't need UNTRAIN_RET Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Borislav Petkov <bp@suse.de>
2022-06-27x86/xen: Rename SYS* entry pointsPeter Zijlstra
Native SYS{CALL,ENTER} entry points are called entry_SYS{CALL,ENTER}_{64,compat}, make sure the Xen versions are named consistently. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Borislav Petkov <bp@suse.de>
2022-06-27objtool: Update Retpoline validationPeter Zijlstra
Update retpoline validation with the new CONFIG_RETPOLINE requirement of not having bare naked RET instructions. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Borislav Petkov <bp@suse.de>
2022-06-06xen/virtio: Enable restricted memory access using Xen grant mappingsJuergen Gross
In order to support virtio in Xen guests add a config option XEN_VIRTIO enabling the user to specify whether in all Xen guests virtio should be able to access memory via Xen grant mappings only on the host side. Also set PLATFORM_VIRTIO_RESTRICTED_MEM_ACCESS feature from the guest initialization code on Arm and x86 if CONFIG_XEN_VIRTIO is enabled. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lore.kernel.org/r/1654197833-25362-5-git-send-email-olekstysh@gmail.com Signed-off-by: Juergen Gross <jgross@suse.com>
2022-05-30Merge tag 'pm-5.19-rc1-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull more power management updates from Rafael Wysocki: "These update the ARM cpufreq drivers and fix up the CPPC cpufreq driver after recent changes, update the OPP code and PM documentation and add power sequences support to the system reboot and power off code. Specifics: - Add Tegra234 cpufreq support (Sumit Gupta) - Clean up and enhance the Mediatek cpufreq driver (Wan Jiabing, Rex-BC Chen, and Jia-Wei Chang) - Fix up the CPPC cpufreq driver after recent changes (Zheng Bin, Pierre Gondois) - Minor update to dt-binding for Qcom's opp-v2-kryo-cpu (Yassine Oudjana) - Use list iterator only inside the list_for_each_entry loop (Xiaomeng Tong, and Jakob Koschel) - New APIs related to finding OPP based on interconnect bandwidth (Krzysztof Kozlowski) - Fix the missing of_node_put() in _bandwidth_supported() (Dan Carpenter) - Cleanups (Krzysztof Kozlowski, and Viresh Kumar) - Add Out of Band mode description to the intel-speed-select utility documentation (Srinivas Pandruvada) - Add power sequences support to the system reboot and power off code and make related platform-specific changes for multiple platforms (Dmitry Osipenko, Geert Uytterhoeven)" * tag 'pm-5.19-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (60 commits) cpufreq: CPPC: Fix unused-function warning cpufreq: CPPC: Fix build error without CONFIG_ACPI_CPPC_CPUFREQ_FIE Documentation: admin-guide: PM: Add Out of Band mode kernel/reboot: Change registration order of legacy power-off handler m68k: virt: Switch to new sys-off handler API kernel/reboot: Add devm_register_restart_handler() kernel/reboot: Add devm_register_power_off_handler() soc/tegra: pmc: Use sys-off handler API to power off Nexus 7 properly reboot: Remove pm_power_off_prepare() regulator: pfuze100: Use devm_register_sys_off_handler() ACPI: power: Switch to sys-off handler API memory: emif: Use kernel_can_power_off() mips: Use do_kernel_power_off() ia64: Use do_kernel_power_off() x86: Use do_kernel_power_off() sh: Use do_kernel_power_off() m68k: Switch to new sys-off handler API powerpc: Use do_kernel_power_off() xen/x86: Use do_kernel_power_off() parisc: Use do_kernel_power_off() ...
2022-05-25Merge tag 'dma-mapping-5.19-2022-05-25' of ↵Linus Torvalds
git://git.infradead.org/users/hch/dma-mapping Pull dma-mapping updates from Christoph Hellwig: - don't over-decrypt memory (Robin Murphy) - takes min align mask into account for the swiotlb max mapping size (Tianyu Lan) - use GFP_ATOMIC in dma-debug (Mikulas Patocka) - fix DMA_ATTR_NO_KERNEL_MAPPING on xen/arm (me) - don't fail on highmem CMA pages in dma_direct_alloc_pages (me) - cleanup swiotlb initialization and share more code with swiotlb-xen (me, Stefano Stabellini) * tag 'dma-mapping-5.19-2022-05-25' of git://git.infradead.org/users/hch/dma-mapping: (23 commits) dma-direct: don't over-decrypt memory swiotlb: max mapping size takes min align mask into account swiotlb: use the right nslabs-derived sizes in swiotlb_init_late swiotlb: use the right nslabs value in swiotlb_init_remap swiotlb: don't panic when the swiotlb buffer can't be allocated dma-debug: change allocation mode from GFP_NOWAIT to GFP_ATIOMIC dma-direct: don't fail on highmem CMA pages in dma_direct_alloc_pages swiotlb-xen: fix DMA_ATTR_NO_KERNEL_MAPPING on arm x86: remove cruft from <asm/dma-mapping.h> swiotlb: remove swiotlb_init_with_tbl and swiotlb_init_late_with_tbl swiotlb: merge swiotlb-xen initialization into swiotlb swiotlb: provide swiotlb_init variants that remap the buffer swiotlb: pass a gfp_mask argument to swiotlb_init_late swiotlb: add a SWIOTLB_ANY flag to lift the low memory restriction swiotlb: make the swiotlb_init interface more useful x86: centralize setting SWIOTLB_FORCE when guest memory encryption is enabled x86: remove the IOMMU table infrastructure MIPS/octeon: use swiotlb_init instead of open coding it arm/xen: don't check for xen_initial_domain() in xen_create_contiguous_region swiotlb: rename swiotlb_late_init_with_default_size ...
2022-05-25Merge back reboot/poweroff notifiers rework for 5.19-rc1.Rafael J. Wysocki
2022-05-23Merge tag 'for-linus-5.19-rc1-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen updates from Juergen Gross: - decouple the PV interface from kernel internals in the Xen scsifront/scsiback pv drivers - harden the Xen scsifront PV driver against a malicious backend driver - simplify Xen PV frontend driver ring page setup - support Xen setups with multiple domains created at boot time to tolerate Xenstore coming up late - two small cleanup patches * tag 'for-linus-5.19-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (29 commits) xen: add support for initializing xenstore later as HVM domain xen: sync xs_wire.h header with upstream xen x86: xen: remove STACK_FRAME_NON_STANDARD from xen_cpuid xen-blk{back,front}: Update contact points for buffer_squeeze_duration_ms and feature_persistent xen/xenbus: eliminate xenbus_grant_ring() xen/sndfront: use xenbus_setup_ring() and xenbus_teardown_ring() xen/usbfront: use xenbus_setup_ring() and xenbus_teardown_ring() xen/scsifront: use xenbus_setup_ring() and xenbus_teardown_ring() xen/pcifront: use xenbus_setup_ring() and xenbus_teardown_ring() xen/drmfront: use xenbus_setup_ring() and xenbus_teardown_ring() xen/tpmfront: use xenbus_setup_ring() and xenbus_teardown_ring() xen/netfront: use xenbus_setup_ring() and xenbus_teardown_ring() xen/blkfront: use xenbus_setup_ring() and xenbus_teardown_ring() xen/xenbus: add xenbus_setup_ring() service function xen: update ring.h xen/shbuf: switch xen-front-pgdir-shbuf to use INVALID_GRANT_REF xen/dmabuf: switch gntdev-dmabuf to use INVALID_GRANT_REF xen/sound: switch xen_snd_front to use INVALID_GRANT_REF xen/drm: switch xen_drm_front to use INVALID_GRANT_REF xen/usb: switch xen-hcd to use INVALID_GRANT_REF ...
2022-05-23Merge tag 'smp-core-2022-05-23' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull CPU hotplug updates from Thomas Gleixner: - Initialize the per-CPU structures during early boot so that the state is consistent from the very beginning. - Make the virtualization hotplug state handling more robust and let the core bringup CPUs which timed out in an earlier attempt again. - Make the x86/xen CPU state tracking consistent on a failed online attempt, so a consecutive bringup does not fall over the inconsistent state. * tag 'smp-core-2022-05-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: cpu/hotplug: Initialise all cpuhp_cpu_state structs earlier cpu/hotplug: Allow the CPU in CPU_UP_PREPARE state to be brought up again. x86/xen: Allow to retry if cpu_initialize_context() failed.
2022-05-19xen/x86: Use do_kernel_power_off()Dmitry Osipenko
Kernel now supports chained power-off handlers. Use do_kernel_power_off() that invokes chained power-off handlers. It also invokes legacy pm_power_off() for now, which will be removed once all drivers will be converted to the new sys-off API. Acked-by: Juergen Gross <jgross@suse.com> Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-05-19x86: xen: remove STACK_FRAME_NON_STANDARD from xen_cpuidMaximilian Heyne
Since commit 4d65adfcd119 ("x86: xen: insn: Decode Xen and KVM emulate-prefix signature"), objtool is able to correctly parse the prefixed instruction in xen_cpuid and emit correct orc unwind information. Hence, marking the function as STACKFRAME_NON_STANDARD is no longer needed. This commit is basically a revert of commit 983bb6d254c7 ("x86/xen: Mark xen_cpuid() stack frame as non-standard"). Signed-off-by: Maximilian Heyne <mheyne@amazon.de> Reviewed-by: Juergen Gross <jgross@suse.com> CC: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://lore.kernel.org/r/20220517162425.100567-1-mheyne@amazon.de Signed-off-by: Juergen Gross <jgross@suse.com>
2022-05-11swiotlb-xen: fix DMA_ATTR_NO_KERNEL_MAPPING on armChristoph Hellwig
swiotlb-xen uses very different ways to allocate coherent memory on x86 vs arm. On the former it allocates memory from the page allocator, while on the later it reuses the dma-direct allocator the handles the complexities of non-coherent DMA on arm platforms. Unfortunately the complexities of trying to deal with the two cases in the swiotlb-xen.c code lead to a bug in the handling of DMA_ATTR_NO_KERNEL_MAPPING on arm. With the DMA_ATTR_NO_KERNEL_MAPPING flag the coherent memory allocator does not actually allocate coherent memory, but just a DMA handle for some memory that is DMA addressable by the device, but which does not have to have a kernel mapping. Thus dereferencing the return value will lead to kernel crashed and memory corruption. Fix this by using the dma-direct allocator directly for arm, which works perfectly fine because on arm swiotlb-xen is only used when the domain is 1:1 mapped, and then simplifying the remaining code to only cater for the x86 case with DMA coherent device. Reported-by: Rahul Singh <Rahul.Singh@arm.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Rahul Singh <rahul.singh@arm.com> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Tested-by: Rahul Singh <rahul.singh@arm.com>
2022-04-19x86/xen: Add ANNOTATE_NOENDBR to startup_xen()Josh Poimboeuf
The startup_xen() kernel entry point is referenced by the ".note.Xen" section, and is the real entry point of the VM. Control transfer is through IRET, which *could* set NEED_ENDBR, however Xen currently does no such thing. Add ANNOTATE_NOENDBR to silence future objtool warnings. Fixes: ed53a0d97192 ("x86/alternative: Use .ibt_endbr_seal to seal indirect calls") Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com> Link: https://lkml.kernel.org/r/a87bd48b06d11ec4b98122a429e71e489b4e48c3.1650300597.git.jpoimboe@redhat.com
2022-04-18x86: remove the IOMMU table infrastructureChristoph Hellwig
The IOMMU table tries to separate the different IOMMUs into different backends, but actually requires various cross calls. Rewrite the code to do the generic swiotlb/swiotlb-xen setup directly in pci-dma.c and then just call into the IOMMU drivers. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2022-04-12x86/xen: Allow to retry if cpu_initialize_context() failed.Boris Ostrovsky
If memory allocation in cpu_initialize_context() fails then it will bring up the VCPU and leave with the corresponding CPU bit set in xen_cpu_initialized_map. The following (presumably successful) CPU bring up will BUG in xen_pv_cpu_up() because nothing for that VCPU would be initialized. Clear the CPU bits, that were set in cpu_initialize_context() in case the memory allocation fails. [ bigeasy: Creating a patch from Boris' email. ] Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20220209080214.1439408-2-bigeasy@linutronix.de
2022-03-28Merge tag 'for-linus-5.18-rc1-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen updates from Juergen Gross: - A bunch of minor cleanups - A fix for kexec in Xen dom0 when executed on a high cpu number - A fix for resuming after suspend of a Xen guest with assigned PCI devices - A fix for a crash due to not disabled preemption when resuming as Xen dom0 * tag 'for-linus-5.18-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen: fix is_xen_pmu() xen: don't hang when resuming PCI device arch:x86:xen: Remove unnecessary assignment in xen_apic_read() xen/grant-table: remove readonly parameter from functions xen/grant-table: remove gnttab_*transfer*() functions drivers/xen: use helper macro __ATTR_RW x86/xen: Fix kerneldoc warning xen: delay xen_hvm_init_time_ops() if kdump is boot on vcpu>=32 xen: use time_is_before_eq_jiffies() instead of open coding it
2022-03-25xen: fix is_xen_pmu()Juergen Gross
is_xen_pmu() is taking the cpu number as parameter, but it is not using it. Instead it just tests whether the Xen PMU initialization on the current cpu did succeed. As this test is done by checking a percpu pointer, preemption needs to be disabled in order to avoid switching the cpu while doing the test. While resuming from suspend() this seems not to be the case: [ 88.082751] ACPI: PM: Low-level resume complete [ 88.087933] ACPI: EC: EC started [ 88.091464] ACPI: PM: Restoring platform NVS memory [ 88.097166] xen_acpi_processor: Uploading Xen processor PM info [ 88.103850] Enabling non-boot CPUs ... [ 88.108128] installing Xen timer for CPU 1 [ 88.112763] BUG: using smp_processor_id() in preemptible [00000000] code: systemd-sleep/7138 [ 88.122256] caller is is_xen_pmu+0x12/0x30 [ 88.126937] CPU: 0 PID: 7138 Comm: systemd-sleep Tainted: G W 5.16.13-2.fc32.qubes.x86_64 #1 [ 88.137939] Hardware name: Star Labs StarBook/StarBook, BIOS 7.97 03/21/2022 [ 88.145930] Call Trace: [ 88.148757] <TASK> [ 88.151193] dump_stack_lvl+0x48/0x5e [ 88.155381] check_preemption_disabled+0xde/0xe0 [ 88.160641] is_xen_pmu+0x12/0x30 [ 88.164441] xen_smp_intr_init_pv+0x75/0x100 Fix that by replacing is_xen_pmu() by a simple boolean variable which reflects the Xen PMU initialization state on cpu 0. Modify xen_pmu_init() to return early in case it is being called for a cpu other than cpu 0 and the boolean variable not being set. Fixes: bf6dfb154d93 ("xen/PMU: PMU emulation code") Reported-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com> Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lore.kernel.org/r/20220325142002.31789-1-jgross@suse.com Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2022-03-15arch:x86:xen: Remove unnecessary assignment in xen_apic_read()jianchunfu
In the function xen_apic_read(), the initialized value of 'ret' is unused because it will be assigned by the function HYPERVISOR_platform_op(), thus remove it. Signed-off-by: jianchunfu <jianchunfu@cmss.chinamobile.com> Link: https://lore.kernel.org/r/20220314070514.2602-1-jianchunfu@cmss.chinamobile.com Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2022-03-15x86/ibt,xen: Sprinkle the ENDBRPeter Zijlstra
Even though Xen currently doesn't advertise IBT, prepare for when it will eventually do so and sprinkle the ENDBR dust accordingly. Even though most of the entry points are IRET like, the CPL0 Hypervisor can set WAIT-FOR-ENDBR and demand ENDBR at these sites. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Link: https://lore.kernel.org/r/20220308154317.873919996@infradead.org
2022-03-15x86/entry,xen: Early rewrite of restore_regs_and_return_to_kernel()Peter Zijlstra
By doing an early rewrite of 'jmp native_iret` in restore_regs_and_return_to_kernel() we can get rid of the last INTERRUPT_RETURN user and paravirt_iret. Suggested-by: Andrew Cooper <Andrew.Cooper3@citrix.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Link: https://lore.kernel.org/r/20220308154317.815039833@infradead.org
2022-03-10x86/xen: Fix kerneldoc warningJiapeng Chong
Fix the following W=1 kernel warnings: arch/x86/xen/setup.c:725: warning: expecting prototype for machine_specific_memory_setup(). Prototype was for xen_memory_setup() instead. Reported-by: Abaci Robot <abaci@linux.alibaba.com> Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lore.kernel.org/r/20220307062554.8334-1-jiapeng.chong@linux.alibaba.com Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2022-03-10xen: delay xen_hvm_init_time_ops() if kdump is boot on vcpu>=32Dongli Zhang
The sched_clock() can be used very early since commit 857baa87b642 ("sched/clock: Enable sched clock early"). In addition, with commit 38669ba205d1 ("x86/xen/time: Output xen sched_clock time from 0"), kdump kernel in Xen HVM guest may panic at very early stage when accessing &__this_cpu_read(xen_vcpu)->time as in below: setup_arch() -> init_hypervisor_platform() -> x86_init.hyper.init_platform = xen_hvm_guest_init() -> xen_hvm_init_time_ops() -> xen_clocksource_read() -> src = &__this_cpu_read(xen_vcpu)->time; This is because Xen HVM supports at most MAX_VIRT_CPUS=32 'vcpu_info' embedded inside 'shared_info' during early stage until xen_vcpu_setup() is used to allocate/relocate 'vcpu_info' for boot cpu at arbitrary address. However, when Xen HVM guest panic on vcpu >= 32, since xen_vcpu_info_reset(0) would set per_cpu(xen_vcpu, cpu) = NULL when vcpu >= 32, xen_clocksource_read() on vcpu >= 32 would panic. This patch calls xen_hvm_init_time_ops() again later in xen_hvm_smp_prepare_boot_cpu() after the 'vcpu_info' for boot vcpu is registered when the boot vcpu is >= 32. This issue can be reproduced on purpose via below command at the guest side when kdump/kexec is enabled: "taskset -c 33 echo c > /proc/sysrq-trigger" The bugfix for PVM is not implemented due to the lack of testing environment. [boris: xen_hvm_init_time_ops() returns on errors instead of jumping to end] Cc: Joe Jin <joe.jin@oracle.com> Signed-off-by: Dongli Zhang <dongli.zhang@oracle.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lore.kernel.org/r/20220302164032.14569-3-dongli.zhang@oracle.com Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2022-02-10xen/x2apic: Fix inconsistent indentingJiapeng Chong
Eliminate the follow smatch warning: arch/x86/xen/enlighten_hvm.c:189 xen_cpu_dead_hvm() warn: inconsistent indenting. 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/20220207103506.102008-1-jiapeng.chong@linux.alibaba.com Signed-off-by: Juergen Gross <jgross@suse.com>
2022-02-10xen/x86: detect support for extended destination IDRoger Pau Monne
Xen allows the usage of some previously reserved bits in the IO-APIC RTE and the MSI address fields in order to store high bits for the target APIC ID. Such feature is already implemented by QEMU/KVM and HyperV, so in order to enable it just add the handler that checks for it's presence. Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Reviewed-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/20220120152527.7524-3-roger.pau@citrix.com Signed-off-by: Juergen Gross <jgross@suse.com>
2022-02-10xen/x86: obtain full video frame buffer address for Dom0 also under EFIJan Beulich
The initial change would not work when Xen was booted from EFI: There is an early exit from the case block in that case. Move the necessary code ahead of that. Fixes: 335e4dd67b48 ("xen/x86: obtain upper 32 bits of video frame buffer address for Dom0") Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/2501ce9d-40e5-b49d-b0e5-435544d17d4a@suse.com Signed-off-by: Juergen Gross <jgross@suse.com>
2022-02-03x86/Xen: streamline (and fix) PV CPU enumerationJan Beulich
This started out with me noticing that "dom0_max_vcpus=<N>" with <N> larger than the number of physical CPUs reported through ACPI tables would not bring up the "excess" vCPU-s. Addressing this is the primary purpose of the change; CPU maps handling is being tidied only as far as is necessary for the change here (with the effect of also avoiding the setting up of too much per-CPU infrastructure, i.e. for CPUs which can never come online). Noticing that xen_fill_possible_map() is called way too early, whereas xen_filter_cpu_maps() is called too late (after per-CPU areas were already set up), and further observing that each of the functions serves only one of Dom0 or DomU, it looked like it was better to simplify this. Use the .get_smp_config hook instead, uniformly for Dom0 and DomU. xen_fill_possible_map() can be dropped altogether, while xen_filter_cpu_maps() is re-purposed but not otherwise changed. Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lore.kernel.org/r/2dbd5f0a-9859-ca2d-085e-a02f7166c610@suse.com Signed-off-by: Juergen Gross <jgross@suse.com>
2022-01-28xen/x2apic: enable x2apic mode when supported for HVMRoger Pau Monne
There's no point in disabling x2APIC mode when running as a Xen HVM guest, just enable it when available. Remove some unneeded wrapping around the detection functions, and simply provide a xen_x2apic_available helper that's a wrapper around x2apic_supported. Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lore.kernel.org/r/20220121090146.13697-1-roger.pau@citrix.com Signed-off-by: Juergen Gross <jgross@suse.com>
2022-01-12Merge tag 'for-linus-5.17-rc1-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen updates from Juergen Gross: - a fix for the Xen gntdev driver - a fix for running as Xen dom0 booted via EFI and the EFI framebuffer being located above 4GB - a series for support of mapping other guest's memory by using zone device when running as Xen guest on Arm * tag 'for-linus-5.17-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: dt-bindings: xen: Clarify "reg" purpose arm/xen: Read extended regions from DT and init Xen resource xen/unpopulated-alloc: Add mechanism to use Xen resource xen/balloon: Bring alloc(free)_xenballooned_pages helpers back arm/xen: Switch to use gnttab_setup_auto_xlat_frames() for DT xen/unpopulated-alloc: Drop check for virt_addr_valid() in fill_list() xen/x86: obtain upper 32 bits of video frame buffer address for Dom0 xen/gntdev: fix unmap notification order
2022-01-12Merge tag 'x86_core_for_v5.17_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 core updates from Borislav Petkov: - Get rid of all the .fixup sections because this generates misleading/wrong stacktraces and confuse RELIABLE_STACKTRACE and LIVEPATCH as the backtrace misses the function which is being fixed up. - Add Straight Line Speculation mitigation support which uses a new compiler switch -mharden-sls= which sticks an INT3 after a RET or an indirect branch in order to block speculation after them. Reportedly, CPUs do speculate behind such insns. - The usual set of cleanups and improvements * tag 'x86_core_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (32 commits) x86/entry_32: Fix segment exceptions objtool: Remove .fixup handling x86: Remove .fixup section x86/word-at-a-time: Remove .fixup usage x86/usercopy: Remove .fixup usage x86/usercopy_32: Simplify __copy_user_intel_nocache() x86/sgx: Remove .fixup usage x86/checksum_32: Remove .fixup usage x86/vmx: Remove .fixup usage x86/kvm: Remove .fixup usage x86/segment: Remove .fixup usage x86/fpu: Remove .fixup usage x86/xen: Remove .fixup usage x86/uaccess: Remove .fixup usage x86/futex: Remove .fixup usage x86/msr: Remove .fixup usage x86/extable: Extend extable functionality x86/entry_32: Remove .fixup usage x86/entry_64: Remove .fixup usage x86/copy_mc_64: Remove .fixup usage ...
2022-01-12Merge tag 'perf_core_for_v5.17_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf updates from Borislav Petkov: "Cleanup of the perf/kvm interaction." * tag 'perf_core_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf: Drop guest callback (un)register stubs KVM: arm64: Drop perf.c and fold its tiny bits of code into arm.c KVM: arm64: Hide kvm_arm_pmu_available behind CONFIG_HW_PERF_EVENTS=y KVM: arm64: Convert to the generic perf callbacks KVM: x86: Move Intel Processor Trace interrupt handler to vmx.c KVM: Move x86's perf guest info callbacks to generic KVM KVM: x86: More precisely identify NMI from guest when handling PMI KVM: x86: Drop current_vcpu for kvm_running_vcpu + kvm_arch_vcpu variable perf/core: Use static_call to optimize perf_guest_info_callbacks perf: Force architectures to opt-in to guest callbacks perf: Add wrappers for invoking guest callbacks perf/core: Rework guest callbacks to prepare for static_call support perf: Drop dead and useless guest "support" from arm, csky, nds32 and riscv perf: Stop pretending that perf can handle multiple guest callbacks KVM: x86: Register Processor Trace interrupt hook iff PT enabled in guest KVM: x86: Register perf callbacks after calling vendor's hardware_setup() perf: Protect perf_guest_cbs with RCU
2022-01-06xen/x86: obtain upper 32 bits of video frame buffer address for Dom0Jan Beulich
The hypervisor has been supplying this information for a couple of major releases. Make use of it. The need to set a flag in the capabilities field also points out that the prior setting of that field from the hypervisor interface's gbl_caps one was wrong, so that code gets deleted (there's also no equivalent of this in native boot code). Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lore.kernel.org/r/a3df8bf3-d044-b7bb-3383-cd5239d6d4af@suse.com Signed-off-by: Juergen Gross <jgross@suse.com>
2021-12-08x86: Prepare asm files for straight-line-speculationPeter Zijlstra
Replace all ret/retq instructions with RET in preparation of making RET a macro. Since AS is case insensitive it's a big no-op without RET defined. find arch/x86/ -name \*.S | while read file do sed -i 's/\<ret[q]*\>/RET/' $file done Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lore.kernel.org/r/20211204134907.905503893@infradead.org
2021-12-03x86/xen: Add xenpv_restore_regs_and_return_to_usermode()Lai Jiangshan
In the native case, PER_CPU_VAR(cpu_tss_rw + TSS_sp0) is the trampoline stack. But XEN pv doesn't use trampoline stack, so PER_CPU_VAR(cpu_tss_rw + TSS_sp0) is also the kernel stack. In that case, source and destination stacks are identical, which means that reusing swapgs_restore_regs_and_return_to_usermode() in XEN pv would cause %rsp to move up to the top of the kernel stack and leave the IRET frame below %rsp. This is dangerous as it can be corrupted if #NMI / #MC hit as either of these events occurring in the middle of the stack pushing would clobber data on the (original) stack. And, with XEN pv, swapgs_restore_regs_and_return_to_usermode() pushing the IRET frame on to the original address is useless and error-prone when there is any future attempt to modify the code. [ bp: Massage commit message. ] Fixes: 7f2590a110b8 ("x86/entry/64: Use a per-CPU trampoline stack for IDT entries") Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lkml.kernel.org/r/20211126101209.8613-4-jiangshanlai@gmail.com
2021-11-17perf: Force architectures to opt-in to guest callbacksSean Christopherson
Introduce GUEST_PERF_EVENTS and require architectures to select it to allow registering and using guest callbacks in perf. This will hopefully make it more difficult for new architectures to add useless "support" for guest callbacks, e.g. via copy+paste. Stubbing out the helpers has the happy bonus of avoiding a load of perf_guest_cbs when GUEST_PERF_EVENTS=n on arm64/x86. Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Link: https://lore.kernel.org/r/20211111020738.2512932-9-seanjc@google.com
2021-11-17perf/core: Rework guest callbacks to prepare for static_call supportLike Xu
To prepare for using static_calls to optimize perf's guest callbacks, replace ->is_in_guest and ->is_user_mode with a new multiplexed hook ->state, tweak ->handle_intel_pt_intr to play nice with being called when there is no active guest, and drop "guest" from ->get_guest_ip. Return '0' from ->state and ->handle_intel_pt_intr to indicate "not in guest" so that DEFINE_STATIC_CALL_RET0 can be used to define the static calls, i.e. no callback == !guest. [sean: extracted from static_call patch, fixed get_ip() bug, wrote changelog] Suggested-by: Peter Zijlstra (Intel) <peterz@infradead.org> Originally-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Like Xu <like.xu@linux.intel.com> Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Link: https://lore.kernel.org/r/20211111020738.2512932-7-seanjc@google.com
2021-11-11x86/smp: Factor out parts of native_smp_prepare_cpus()Boris Ostrovsky
Commit 66558b730f25 ("sched: Add cluster scheduler level for x86") introduced cpu_l2c_shared_map mask which is expected to be initialized by smp_op.smp_prepare_cpus(). That commit only updated native_smp_prepare_cpus() version but not xen_pv_smp_prepare_cpus(). As result Xen PV guests crash in set_cpu_sibling_map(). While the new mask can be allocated in xen_pv_smp_prepare_cpus() one can see that both versions of smp_prepare_cpus ops share a number of common operations that can be factored out. So do that instead. Fixes: 66558b730f25 ("sched: Add cluster scheduler level for x86") Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Juergen Gross <jgross@suse.com> Link: https://lkml.kernel.org/r/1635896196-18961-1-git-send-email-boris.ostrovsky@oracle.com
2021-11-10Merge tag 'for-linus-5.16b-rc1-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen updates from Juergen Gross: - a series to speed up the boot of Xen PV guests - some cleanups in Xen related code - replacement of license texts with the appropriate SPDX headers and fixing of wrong SPDX headers in Xen header files - a small series making paravirtualized interrupt masking much simpler and at the same time removing complaints of objtool - a fix for Xen ballooning hogging workqueues for too long - enablement of the Xen pciback driver for Arm - some further small fixes/enhancements * tag 'for-linus-5.16b-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (22 commits) xen/balloon: fix unused-variable warning xen/balloon: rename alloc/free_xenballooned_pages xen/balloon: add late_initcall_sync() for initial ballooning done x86/xen: remove 32-bit awareness from startup_xen xen: remove highmem remnants xen: allow pv-only hypercalls only with CONFIG_XEN_PV x86/xen: remove 32-bit pv leftovers xen-pciback: allow compiling on other archs than x86 x86/xen: switch initial pvops IRQ functions to dummy ones x86/xen: remove xen_have_vcpu_info_placement flag x86/pvh: add prototype for xen_pvh_init() xen: Fix implicit type conversion xen: fix wrong SPDX headers of Xen related headers xen/pvcalls-back: Remove redundant 'flush_workqueue()' calls x86/xen: Remove redundant irq_enter/exit() invocations xen-pciback: Fix return in pm_ctrl_init() xen/x86: restrict PV Dom0 identity mapping xen/x86: there's no highmem anymore in PV mode xen/x86: adjust handling of the L3 user vsyscall special page table xen/x86: adjust xen_set_fixmap() ...
2021-11-09Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge more updates from Andrew Morton: "87 patches. Subsystems affected by this patch series: mm (pagecache and hugetlb), procfs, misc, MAINTAINERS, lib, checkpatch, binfmt, kallsyms, ramfs, init, codafs, nilfs2, hfs, crash_dump, signals, seq_file, fork, sysvfs, kcov, gdb, resource, selftests, and ipc" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (87 commits) ipc/ipc_sysctl.c: remove fallback for !CONFIG_PROC_SYSCTL ipc: check checkpoint_restore_ns_capable() to modify C/R proc files selftests/kselftest/runner/run_one(): allow running non-executable files virtio-mem: disallow mapping virtio-mem memory via /dev/mem kernel/resource: disallow access to exclusive system RAM regions kernel/resource: clean up and optimize iomem_is_exclusive() scripts/gdb: handle split debug for vmlinux kcov: replace local_irq_save() with a local_lock_t kcov: avoid enable+disable interrupts if !in_task() kcov: allocate per-CPU memory on the relevant node Documentation/kcov: define `ip' in the example Documentation/kcov: include types.h in the example sysv: use BUILD_BUG_ON instead of runtime check kernel/fork.c: unshare(): use swap() to make code cleaner seq_file: fix passing wrong private data seq_file: move seq_escape() to a header signal: remove duplicate include in signal.h crash_dump: remove duplicate include in crash_dump.h crash_dump: fix boolreturn.cocci warning hfs/hfsplus: use WARN_ON for sanity check ...
2021-11-09proc/vmcore: convert oldmem_pfn_is_ram callback to more generic vmcore callbacksDavid Hildenbrand
Let's support multiple registered callbacks, making sure that registering vmcore callbacks cannot fail. Make the callback return a bool instead of an int, handling how to deal with errors internally. Drop unused HAVE_OLDMEM_PFN_IS_RAM. We soon want to make use of this infrastructure from other drivers: virtio-mem, registering one callback for each virtio-mem device, to prevent reading unplugged virtio-mem memory. Handle it via a generic vmcore_cb structure, prepared for future extensions: for example, once we support virtio-mem on s390x where the vmcore is completely constructed in the second kernel, we want to detect and add plugged virtio-mem memory ranges to the vmcore in order for them to get dumped properly. Handle corner cases that are unexpected and shouldn't happen in sane setups: registering a callback after the vmcore has already been opened (warn only) and unregistering a callback after the vmcore has already been opened (warn and essentially read only zeroes from that point on). Link: https://lkml.kernel.org/r/20211005121430.30136-6-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Cc: Baoquan He <bhe@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Dave Young <dyoung@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Oscar Salvador <osalvador@suse.de> Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-09x86/xen: print a warning when HVMOP_get_mem_type failsDavid Hildenbrand
HVMOP_get_mem_type is not expected to fail, "This call failing is indication of something going quite wrong and it would be good to know about this." [1] Let's add a pr_warn_once(). Link: https://lkml.kernel.org/r/3b935aa0-6d85-0bcd-100e-15098add3c4c@oracle.com [1] Link: https://lkml.kernel.org/r/20211005121430.30136-4-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Suggested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Baoquan He <bhe@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Young <dyoung@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Oscar Salvador <osalvador@suse.de> Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-09x86/xen: simplify xen_oldmem_pfn_is_ram()David Hildenbrand
Let's simplify return handling. Link: https://lkml.kernel.org/r/20211005121430.30136-3-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Cc: Baoquan He <bhe@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Dave Young <dyoung@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Oscar Salvador <osalvador@suse.de> Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-09x86/xen: update xen_oldmem_pfn_is_ram() documentationDavid Hildenbrand
After removing /dev/kmem, sanitizing /proc/kcore and handling /dev/mem, this series tackles the last sane way how a VM could accidentially access logically unplugged memory managed by a virtio-mem device: /proc/vmcore When dumping memory via "makedumpfile", PG_offline pages, used by virtio-mem to flag logically unplugged memory, are already properly excluded; however, especially when accessing/copying /proc/vmcore "the usual way", we can still end up reading logically unplugged memory part of a virtio-mem device. Patch #1-#3 are cleanups. Patch #4 extends the existing oldmem_pfn_is_ram mechanism. Patch #5-#7 are virtio-mem refactorings for patch #8, which implements the virtio-mem logic to query the state of device blocks. Patch #8: "Although virtio-mem currently supports reading unplugged memory in the hypervisor, this will change in the future, indicated to the device via a new feature flag. We similarly sanitized /proc/kcore access recently. [...] Distributions that support virtio-mem+kdump have to make sure that the virtio_mem module will be part of the kdump kernel or the kdump initrd; dracut was recently [2] extended to include virtio-mem in the generated initrd. As long as no special kdump kernels are used, this will automatically make sure that virtio-mem will be around in the kdump initrd and sanitize /proc/vmcore access -- with dracut" This is the last remaining bit to support VIRTIO_MEM_F_UNPLUGGED_INACCESSIBLE [3] in the Linux implementation of virtio-mem. Note: this is best-effort. We'll never be able to control what runs inside the second kernel, really, but we also don't have to care: we only care about sane setups where we don't want our VM getting zapped once we touch the wrong memory location while dumping. While we usually expect sane setups to use "makedumfile", nothing really speaks against just copying /proc/vmcore, especially in environments where HWpoisioning isn't typically expected. Also, we really don't want to put all our trust completely on the memmap, so sanitizing also makes sense when just using "makedumpfile". [1] https://lkml.kernel.org/r/20210526093041.8800-1-david@redhat.com [2] https://github.com/dracutdevs/dracut/pull/1157 [3] https://lists.oasis-open.org/archives/virtio-comment/202109/msg00021.html This patch (of 9): The callback is only used for the vmcore nowadays. Link: https://lkml.kernel.org/r/20211005121430.30136-1-david@redhat.com Link: https://lkml.kernel.org/r/20211005121430.30136-2-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Boris Ostrovsky <boris.ostrvsky@oracle.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Juergen Gross <jgross@suse.com> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Dave Young <dyoung@redhat.com> Cc: Baoquan He <bhe@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Mike Rapoport <rppt@kernel.org> Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-06Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge misc updates from Andrew Morton: "257 patches. Subsystems affected by this patch series: scripts, ocfs2, vfs, and mm (slab-generic, slab, slub, kconfig, dax, kasan, debug, pagecache, gup, swap, memcg, pagemap, mprotect, mremap, iomap, tracing, vmalloc, pagealloc, memory-failure, hugetlb, userfaultfd, vmscan, tools, memblock, oom-kill, hugetlbfs, migration, thp, readahead, nommu, ksm, vmstat, madvise, memory-hotplug, rmap, zsmalloc, highmem, zram, cleanups, kfence, and damon)" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (257 commits) mm/damon: remove return value from before_terminate callback mm/damon: fix a few spelling mistakes in comments and a pr_debug message mm/damon: simplify stop mechanism Docs/admin-guide/mm/pagemap: wordsmith page flags descriptions Docs/admin-guide/mm/damon/start: simplify the content Docs/admin-guide/mm/damon/start: fix a wrong link Docs/admin-guide/mm/damon/start: fix wrong example commands mm/damon/dbgfs: add adaptive_targets list check before enable monitor_on mm/damon: remove unnecessary variable initialization Documentation/admin-guide/mm/damon: add a document for DAMON_RECLAIM mm/damon: introduce DAMON-based Reclamation (DAMON_RECLAIM) selftests/damon: support watermarks mm/damon/dbgfs: support watermarks mm/damon/schemes: activate schemes based on a watermarks mechanism tools/selftests/damon: update for regions prioritization of schemes mm/damon/dbgfs: support prioritization weights mm/damon/vaddr,paddr: support pageout prioritization mm/damon/schemes: prioritize regions within the quotas mm/damon/selftests: support schemes quotas mm/damon/dbgfs: support quotas of schemes ...
2021-11-06memblock: use memblock_free for freeing virtual pointersMike Rapoport
Rename memblock_free_ptr() to memblock_free() and use memblock_free() when freeing a virtual pointer so that memblock_free() will be a counterpart of memblock_alloc() The callers are updated with the below semantic patch and manual addition of (void *) casting to pointers that are represented by unsigned long variables. @@ identifier vaddr; expression size; @@ ( - memblock_phys_free(__pa(vaddr), size); + memblock_free(vaddr, size); | - memblock_free_ptr(vaddr, size); + memblock_free(vaddr, size); ) [sfr@canb.auug.org.au: fixup] Link: https://lkml.kernel.org/r/20211018192940.3d1d532f@canb.auug.org.au Link: https://lkml.kernel.org/r/20210930185031.18648-7-rppt@kernel.org Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Juergen Gross <jgross@suse.com> Cc: Shahab Vahedi <Shahab.Vahedi@synopsys.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-06memblock: rename memblock_free to memblock_phys_freeMike Rapoport
Since memblock_free() operates on a physical range, make its name reflect it and rename it to memblock_phys_free(), so it will be a logical counterpart to memblock_phys_alloc(). The callers are updated with the below semantic patch: @@ expression addr; expression size; @@ - memblock_free(addr, size); + memblock_phys_free(addr, size); Link: https://lkml.kernel.org/r/20210930185031.18648-6-rppt@kernel.org Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Juergen Gross <jgross@suse.com> Cc: Shahab Vahedi <Shahab.Vahedi@synopsys.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-06xen/x86: free_p2m_page: use memblock_free_ptr() to free a virtual pointerMike Rapoport
free_p2m_page() wrongly passes a virtual pointer to memblock_free() that treats it as a physical address. Call memblock_free_ptr() instead that gets a virtual address to free the memory. Link: https://lkml.kernel.org/r/20210930185031.18648-3-rppt@kernel.org Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Reviewed-by: Juergen Gross <jgross@suse.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Shahab Vahedi <Shahab.Vahedi@synopsys.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>