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2023-08-05Merge tag 'hyperv-fixes-signed-20230804' of ↵Linus Torvalds6-26/+33
git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux Pull hyperv fixes from Wei Liu: - Fix a bug in a python script for Hyper-V (Ani Sinha) - Workaround a bug in Hyper-V when IBT is enabled (Michael Kelley) - Fix an issue parsing MP table when Linux runs in VTL2 (Saurabh Sengar) - Several cleanup patches (Nischala Yelchuri, Kameron Carr, YueHaibing, ZhiHu) * tag 'hyperv-fixes-signed-20230804' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux: Drivers: hv: vmbus: Remove unused extern declaration vmbus_ontimer() x86/hyperv: add noop functions to x86_init mpparse functions vmbus_testing: fix wrong python syntax for integer value comparison x86/hyperv: fix a warning in mshyperv.h x86/hyperv: Disable IBT when hypercall page lacks ENDBR instruction x86/hyperv: Improve code for referencing hyperv_pcpu_input_arg Drivers: hv: Change hv_free_hyperv_page() to take void * argument
2023-08-03x86/hyperv: add noop functions to x86_init mpparse functionsSaurabh Sengar1-0/+4
Hyper-V can run VMs at different privilege "levels" known as Virtual Trust Levels (VTL). Sometimes, it chooses to run two different VMs at different levels but they share some of their address space. In such setups VTL2 (higher level VM) has visibility of all of the VTL0 (level 0) memory space. When the CONFIG_X86_MPPARSE is enabled for VTL2, the VTL2 kernel performs a search within the low memory to locate MP tables. However, in systems where VTL0 manages the low memory and may contain valid tables, this scanning can result in incorrect MP table information being provided to the VTL2 kernel, mistakenly considering VTL0's MP table as its own Add noop functions to avoid MP parse scan by VTL2. Signed-off-by: Saurabh Sengar <ssengar@linux.microsoft.com> Acked-by: Dave Hansen <dave.hansen@linux.intel.com> Link: https://lore.kernel.org/r/1687537688-5397-1-git-send-email-ssengar@linux.microsoft.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2023-07-24x86/hyperv: Disable IBT when hypercall page lacks ENDBR instructionMichael Kelley1-0/+21
On hardware that supports Indirect Branch Tracking (IBT), Hyper-V VMs with ConfigVersion 9.3 or later support IBT in the guest. However, current versions of Hyper-V have a bug in that there's not an ENDBR64 instruction at the beginning of the hypercall page. Since hypercalls are made with an indirect call to the hypercall page, all hypercall attempts fail with an exception and Linux panics. A Hyper-V fix is in progress to add ENDBR64. But guard against the Linux panic by clearing X86_FEATURE_IBT if the hypercall page doesn't start with ENDBR. The VM will boot and run without IBT. If future Linux 32-bit kernels were to support IBT, additional hypercall page hackery would be needed to make IBT work for such kernels in a Hyper-V VM. Cc: stable@vger.kernel.org Signed-off-by: Michael Kelley <mikelley@microsoft.com> Link: https://lore.kernel.org/r/1690001476-98594-1-git-send-email-mikelley@microsoft.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2023-06-28x86/hyperv: Improve code for referencing hyperv_pcpu_input_argNischala Yelchuri4-26/+8
Several places in code for Hyper-V reference the per-CPU variable hyperv_pcpu_input_arg. Older code uses a multi-line sequence to reference the variable, and usually includes a cast. Newer code does a much simpler direct assignment. The latter is preferable as the complexity of the older code is unnecessary. Update older code to use the simpler direct assignment. Signed-off-by: Nischala Yelchuri <niyelchu@linux.microsoft.com> Link: https://lore.kernel.org/r/1687286438-9421-1-git-send-email-niyelchu@linux.microsoft.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2023-06-27Merge tag 'x86_sev_for_v6.5' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 SEV updates from Borislav Petkov: - Some SEV and CC platform helpers cleanup and simplifications now that the usage patterns are becoming apparent [ I'm sure I'm the only one that has gets confused by all the TLAs, but in case there are others: here SEV is AMD's "Secure Encrypted Virtualization" and CC is generic "Confidential Computing". There's also Intel SGX (Software Guard Extensions) and TDX (Trust Domain Extensions), along with all the vendor memory encryption extensions (SME, TSME, TME, and WTF). And then we have arm64 with RMA and CCA, and I probably forgot another dozen or so related acronyms - Linus ] * tag 'x86_sev_for_v6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/coco: Get rid of accessor functions x86/sev: Get rid of special sev_es_enable_key x86/coco: Mark cc_platform_has() and descendants noinstr
2023-06-27Merge tag 'x86_mtrr_for_v6.5' of ↵Linus Torvalds1-0/+4
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
2023-06-18x86/hyperv: Fix hyperv_pcpu_input_arg handling when CPUs go online/offlineMichael Kelley1-1/+1
These commits a494aef23dfc ("PCI: hv: Replace retarget_msi_interrupt_params with hyperv_pcpu_input_arg") 2c6ba4216844 ("PCI: hv: Enable PCI pass-thru devices in Confidential VMs") update the Hyper-V virtual PCI driver to use the hyperv_pcpu_input_arg because that memory will be correctly marked as decrypted or encrypted for all VM types (CoCo or normal). But problems ensue when CPUs in the VM go online or offline after virtual PCI devices have been configured. When a CPU is brought online, the hyperv_pcpu_input_arg for that CPU is initialized by hv_cpu_init() running under state CPUHP_AP_ONLINE_DYN. But this state occurs after state CPUHP_AP_IRQ_AFFINITY_ONLINE, which may call the virtual PCI driver and fault trying to use the as yet uninitialized hyperv_pcpu_input_arg. A similar problem occurs in a CoCo VM if the MMIO read and write hypercalls are used from state CPUHP_AP_IRQ_AFFINITY_ONLINE. When a CPU is taken offline, IRQs may be reassigned in state CPUHP_TEARDOWN_CPU. Again, the virtual PCI driver may fault trying to use the hyperv_pcpu_input_arg that has already been freed by a higher state. Fix the onlining problem by adding state CPUHP_AP_HYPERV_ONLINE immediately after CPUHP_AP_ONLINE_IDLE (similar to CPUHP_AP_KVM_ONLINE) and before CPUHP_AP_IRQ_AFFINITY_ONLINE. Use this new state for Hyper-V initialization so that hyperv_pcpu_input_arg is allocated early enough. Fix the offlining problem by not freeing hyperv_pcpu_input_arg when a CPU goes offline. Retain the allocated memory, and reuse it if the CPU comes back online later. Signed-off-by: Michael Kelley <mikelley@microsoft.com> Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com> Acked-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Dexuan Cui <decui@microsoft.com> Link: https://lore.kernel.org/r/1684862062-51576-1-git-send-email-mikelley@microsoft.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2023-06-01x86/hyperv: Set MTRR state when running as SEV-SNP Hyper-V guestJuergen Gross1-0/+4
In order to avoid mappings using the UC- cache attribute, set the MTRR state to use WB caching as the default. This is needed in order to cope with the fact that PAT is enabled, while MTRRs are not supported by the hypervisor. Fixes: 90b926e68f50 ("x86/pat: Fix pat_x_mtrr_type() for MTRR disabled case") Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Tested-by: Michael Kelley <mikelley@microsoft.com> Link: https://lore.kernel.org/r/20230502120931.20719-5-jgross@suse.com Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
2023-05-09x86/coco: Get rid of accessor functionsBorislav Petkov (AMD)1-1/+1
cc_vendor is __ro_after_init and thus can be used directly. No functional changes. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20230508121957.32341-1-bp@alien8.de
2023-05-08x86/hyperv/vtl: Add noop for realmode pointersSaurabh Sengar1-0/+2
Assign the realmode pointers to noop, instead of NULL to fix kernel panic. Signed-off-by: Saurabh Sengar <ssengar@linux.microsoft.com> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Link: https://lore.kernel.org/r/1682331016-22561-1-git-send-email-ssengar@linux.microsoft.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2023-04-29Merge tag 'objtool-core-2023-04-27' of ↵Linus Torvalds1-1/+1
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 ...
2023-04-18x86/hyperv: VTL support for Hyper-VSaurabh Sengar2-0/+228
Virtual Trust Levels (VTL) helps enable Hyper-V Virtual Secure Mode (VSM) feature. VSM is a set of hypervisor capabilities and enlightenments offered to host and guest partitions which enable the creation and management of new security boundaries within operating system software. VSM achieves and maintains isolation through VTLs. Add early initialization for Virtual Trust Levels (VTL). This includes initializing the x86 platform for VTL and enabling boot support for secondary CPUs to start in targeted VTL context. For now, only enable the code for targeted VTL level as 2. When starting an AP at a VTL other than VTL0, the AP must start directly in 64-bit mode, bypassing the usual 16-bit -> 32-bit -> 64-bit mode transition sequence that occurs after waking up an AP with SIPI whose vector points to the 16-bit AP startup trampoline code. Signed-off-by: Saurabh Sengar <ssengar@linux.microsoft.com> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Reviewed-by: Stanislav Kinsburskii <stanislav.kinsburskii@gmail.com> Link: https://lore.kernel.org/r/1681192532-15460-6-git-send-email-ssengar@linux.microsoft.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2023-04-17x86/hyperv: Exclude lazy TLB mode CPUs from enlightened TLB flushesMichael Kelley1-1/+10
In the case where page tables are not freed, native_flush_tlb_multi() does not do a remote TLB flush on CPUs in lazy TLB mode because the CPU will flush itself at the next context switch. By comparison, the Hyper-V enlightened TLB flush does not exclude CPUs in lazy TLB mode and so performs unnecessary flushes. If we're not freeing page tables, add logic to test for lazy TLB mode when adding CPUs to the input argument to the Hyper-V TLB flush hypercall. Exclude lazy TLB mode CPUs so the behavior matches native_flush_tlb_multi() and the unnecessary flushes are avoided. Handle both the <=64 vCPU case and the _ex case for >64 vCPUs. Signed-off-by: Michael Kelley <mikelley@microsoft.com> Link: https://lore.kernel.org/r/1679922967-26582-3-git-send-email-mikelley@microsoft.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2023-04-17x86/hyperv: Add callback filter to cpumask_to_vpset()Michael Kelley1-4/+8
When copying CPUs from a Linux cpumask to a Hyper-V VPset, cpumask_to_vpset() currently has a "_noself" variant that doesn't copy the current CPU to the VPset. Generalize this variant by replacing it with a "_skip" variant having a callback function that is invoked for each CPU to decide if that CPU should be copied. Update the one caller of cpumask_to_vpset_noself() to use the new "_skip" variant instead. No functional change. Signed-off-by: Michael Kelley <mikelley@microsoft.com> Link: https://lore.kernel.org/r/1679922967-26582-2-git-send-email-mikelley@microsoft.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2023-04-17Drivers: hv: Don't remap addresses that are above shared_gpa_boundaryMichael Kelley1-2/+5
With the vTOM bit now treated as a protection flag and not part of the physical address, avoid remapping physical addresses with vTOM set since technically such addresses aren't valid. Use ioremap_cache() instead of memremap() to ensure that the mapping provides decrypted access, which will correctly set the vTOM bit as a protection flag. While this change is not required for correctness with the current implementation of memremap(), for general code hygiene it's better to not depend on the mapping functions doing something reasonable with a physical address that is out-of-range. While here, fix typos in two error messages. Signed-off-by: Michael Kelley <mikelley@microsoft.com> Reviewed-by: Tianyu Lan <Tianyu.Lan@microsoft.com> Link: https://lore.kernel.org/r/1679838727-87310-12-git-send-email-mikelley@microsoft.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2023-04-17hv_netvsc: Remove second mapping of send and recv buffersMichael Kelley1-28/+0
With changes to how Hyper-V guest VMs flip memory between private (encrypted) and shared (decrypted), creating a second kernel virtual mapping for shared memory is no longer necessary. Everything needed for the transition to shared is handled by set_memory_decrypted(). As such, remove the code to create and manage the second mapping for the pre-allocated send and recv buffers. This mapping is the last user of hv_map_memory()/hv_unmap_memory(), so delete these functions as well. Finally, hv_map_memory() is the last user of vmap_pfn() in Hyper-V guest code, so remove the Kconfig selection of VMAP_PFN. Signed-off-by: Michael Kelley <mikelley@microsoft.com> Reviewed-by: Tianyu Lan <Tianyu.Lan@microsoft.com> Link: https://lore.kernel.org/r/1679838727-87310-11-git-send-email-mikelley@microsoft.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2023-04-14x86/hyperv: Mark hv_ghcb_terminate() as noreturnGuilherme G. Piccoli1-1/+1
Annotate the function prototype and definition as noreturn to prevent objtool warnings like: vmlinux.o: warning: objtool: hyperv_init+0x55c: unreachable instruction Also, as per Josh's suggestion, add it to the global_noreturns list. As a comparison, an objdump output without the annotation: [...] 1b63: mov $0x1,%esi 1b68: xor %edi,%edi 1b6a: callq ffffffff8102f680 <hv_ghcb_terminate> 1b6f: jmpq ffffffff82f217ec <hyperv_init+0x9c> # unreachable 1b74: cmpq $0xffffffffffffffff,-0x702a24(%rip) [...] Now, after adding the __noreturn to the function prototype: [...] 17df: callq ffffffff8102f6d0 <hv_ghcb_negotiate_protocol> 17e4: test %al,%al 17e6: je ffffffff82f21bb9 <hyperv_init+0x469> [...] <many insns> 1bb9: mov $0x1,%esi 1bbe: xor %edi,%edi 1bc0: callq ffffffff8102f680 <hv_ghcb_terminate> 1bc5: nopw %cs:0x0(%rax,%rax,1) # end of function Reported-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Guilherme G. Piccoli <gpiccoli@igalia.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Link: https://lore.kernel.org/r/32453a703dfcf0d007b473c9acbf70718222b74b.1681342859.git.jpoimboe@kernel.org
2023-03-27x86/hyperv: Change vTOM handling to use standard coco mechanismsMichael Kelley2-22/+61
Hyper-V guests on AMD SEV-SNP hardware have the option of using the "virtual Top Of Memory" (vTOM) feature specified by the SEV-SNP architecture. With vTOM, shared vs. private memory accesses are controlled by splitting the guest physical address space into two halves. vTOM is the dividing line where the uppermost bit of the physical address space is set; e.g., with 47 bits of guest physical address space, vTOM is 0x400000000000 (bit 46 is set). Guest physical memory is accessible at two parallel physical addresses -- one below vTOM and one above vTOM. Accesses below vTOM are private (encrypted) while accesses above vTOM are shared (decrypted). In this sense, vTOM is like the GPA.SHARED bit in Intel TDX. Support for Hyper-V guests using vTOM was added to the Linux kernel in two patch sets[1][2]. This support treats the vTOM bit as part of the physical address. For accessing shared (decrypted) memory, these patch sets create a second kernel virtual mapping that maps to physical addresses above vTOM. A better approach is to treat the vTOM bit as a protection flag, not as part of the physical address. This new approach is like the approach for the GPA.SHARED bit in Intel TDX. Rather than creating a second kernel virtual mapping, the existing mapping is updated using recently added coco mechanisms. When memory is changed between private and shared using set_memory_decrypted() and set_memory_encrypted(), the PTEs for the existing kernel mapping are changed to add or remove the vTOM bit in the guest physical address, just as with TDX. The hypercalls to change the memory status on the host side are made using the existing callback mechanism. Everything just works, with a minor tweak to map the IO-APIC to use private accesses. To accomplish the switch in approach, the following must be done: * Update Hyper-V initialization to set the cc_mask based on vTOM and do other coco initialization. * Update physical_mask so the vTOM bit is no longer treated as part of the physical address * Remove CC_VENDOR_HYPERV and merge the associated vTOM functionality under CC_VENDOR_AMD. Update cc_mkenc() and cc_mkdec() to set/clear the vTOM bit as a protection flag. * Code already exists to make hypercalls to inform Hyper-V about pages changing between shared and private. Update this code to run as a callback from __set_memory_enc_pgtable(). * Remove the Hyper-V special case from __set_memory_enc_dec() * Remove the Hyper-V specific call to swiotlb_update_mem_attributes() since mem_encrypt_init() will now do it. * Add a Hyper-V specific implementation of the is_private_mmio() callback that returns true for the IO-APIC and vTPM MMIO addresses [1] https://lore.kernel.org/all/20211025122116.264793-1-ltykernel@gmail.com/ [2] https://lore.kernel.org/all/20211213071407.314309-1-ltykernel@gmail.com/ [ bp: Touchups. ] Signed-off-by: Michael Kelley <mikelley@microsoft.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/1679838727-87310-7-git-send-email-mikelley@microsoft.com
2023-03-27Drivers: hv: Explicitly request decrypted in vmap_pfn() callsMichael Kelley1-1/+1
Update vmap_pfn() calls to explicitly request that the mapping be for decrypted access to the memory. There's no change in functionality since the PFNs passed to vmap_pfn() are above the shared_gpa_boundary, implicitly producing a decrypted mapping. But explicitly requesting "decrypted" allows the code to work before and after changes that cause vmap_pfn() to mask the PFNs to being below the shared_gpa_boundary. Signed-off-by: Michael Kelley <mikelley@microsoft.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Tianyu Lan <Tianyu.Lan@microsoft.com> Link: https://lore.kernel.org/r/1679838727-87310-4-git-send-email-mikelley@microsoft.com
2023-03-27x86/hyperv: Reorder code to facilitate future workMichael Kelley1-34/+34
Reorder some code to facilitate future work. No functional change. Signed-off-by: Michael Kelley <mikelley@microsoft.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Tianyu Lan <Tianyu.Lan@microsoft.com> Link: https://lore.kernel.org/r/1679838727-87310-3-git-send-email-mikelley@microsoft.com
2022-11-29x86/hyperv: Remove unregister syscore call from Hyper-V cleanupGaurav Kohli1-2/+0
Hyper-V cleanup code comes under panic path where preemption and irq is already disabled. So calling of unregister_syscore_ops might schedule out the thread even for the case where mutex lock is free. hyperv_cleanup unregister_syscore_ops mutex_lock(&syscore_ops_lock) might_sleep Here might_sleep might schedule out this thread, where voluntary preemption config is on and this thread will never comes back. And also this was added earlier to maintain the symmetry which is not required as this can comes during crash shutdown path only. To prevent the same, removing unregister_syscore_ops function call. Signed-off-by: Gaurav Kohli <gauravkohli@linux.microsoft.com> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Link: https://lore.kernel.org/r/1669443291-2575-1-git-send-email-gauravkohli@linux.microsoft.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2022-11-28clocksource: hyper-v: Add TSC page support for root partitionStanislav Kinsburskiy1-0/+2
Microsoft Hypervisor root partition has to map the TSC page specified by the hypervisor, instead of providing the page to the hypervisor like it's done in the guest partitions. However, it's too early to map the page when the clock is initialized, so, the actual mapping is happening later. Signed-off-by: Stanislav Kinsburskiy <stanislav.kinsburskiy@gmail.com> CC: "K. Y. Srinivasan" <kys@microsoft.com> CC: Haiyang Zhang <haiyangz@microsoft.com> CC: Wei Liu <wei.liu@kernel.org> CC: Dexuan Cui <decui@microsoft.com> CC: Thomas Gleixner <tglx@linutronix.de> CC: Ingo Molnar <mingo@redhat.com> CC: Borislav Petkov <bp@alien8.de> CC: Dave Hansen <dave.hansen@linux.intel.com> CC: x86@kernel.org CC: "H. Peter Anvin" <hpa@zytor.com> CC: Daniel Lezcano <daniel.lezcano@linaro.org> CC: linux-hyperv@vger.kernel.org CC: linux-kernel@vger.kernel.org Reviewed-by: Michael Kelley <mikelley@microsoft.com> Reviewed-by: Anirudh Rayabharam <anrayabh@linux.microsoft.com> Link: https://lore.kernel.org/r/166759443644.385891.15921594265843430260.stgit@skinsburskii-cloud-desktop.internal.cloudapp.net Signed-off-by: Wei Liu <wei.liu@kernel.org>
2022-11-12x86/hyperv: Restore VP assist page after cpu offlining/onliningVitaly Kuznetsov1-28/+26
Commit e5d9b714fe40 ("x86/hyperv: fix root partition faults when writing to VP assist page MSR") moved 'wrmsrl(HV_X64_MSR_VP_ASSIST_PAGE)' under 'if (*hvp)' condition. This works for root partition as hv_cpu_die() does memunmap() and sets 'hv_vp_assist_page[cpu]' to NULL but breaks non-root partitions as hv_cpu_die() doesn't free 'hv_vp_assist_page[cpu]' for them. This causes VP assist page to remain unset after CPU offline/online cycle: $ rdmsr -p 24 0x40000073 10212f001 $ echo 0 > /sys/devices/system/cpu/cpu24/online $ echo 1 > /sys/devices/system/cpu/cpu24/online $ rdmsr -p 24 0x40000073 0 Fix the issue by always writing to HV_X64_MSR_VP_ASSIST_PAGE in hv_cpu_init(). Note, checking 'if (!*hvp)', for root partition is pointless as hv_cpu_die() always sets 'hv_vp_assist_page[cpu]' to NULL (and it's also NULL initially). Note: the fact that 'hv_vp_assist_page[cpu]' is reset to NULL may present a (potential) issue for KVM. While Hyper-V uses CPUHP_AP_ONLINE_DYN stage in CPU hotplug, KVM uses CPUHP_AP_KVM_STARTING which comes earlier in CPU teardown sequence. It is theoretically possible that Enlightened VMCS is still in use. It is unclear if the issue is real and if using KVM with Hyper-V root partition is even possible. While on it, drop the unneeded smp_processor_id() call from hv_cpu_init(). Fixes: e5d9b714fe40 ("x86/hyperv: fix root partition faults when writing to VP assist page MSR") Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Link: https://lore.kernel.org/r/20221103190601.399343-1-vkuznets@redhat.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2022-11-03x86/hyperv: fix invalid writes to MSRs during root partition kexecAnirudh Rayabharam1-4/+7
hyperv_cleanup resets the hypercall page by setting the MSR to 0. However, the root partition is not allowed to write to the GPA bits of the MSR. Instead, it uses the hypercall page provided by the MSR. Similar is the case with the reference TSC MSR. Clear only the enable bit instead of zeroing the entire MSR to make the code valid for root partition too. Signed-off-by: Anirudh Rayabharam <anrayabh@linux.microsoft.com> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Link: https://lore.kernel.org/r/20221027095729.1676394-3-anrayabh@linux.microsoft.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2022-10-27x86/hyperv: Remove BUG_ON() for kmap_local_page()Zhao Liu1-5/+3
The commit 154fb14df7a3c ("x86/hyperv: Replace kmap() with kmap_local_page()") keeps the BUG_ON() to check if kmap_local_page() fails. But in fact, kmap_local_page() always returns a valid kernel address and won't return NULL here. It will BUG on its own if it fails. [1] So directly use memcpy_to_page() which creates local mapping to copy. [1]: https://lore.kernel.org/lkml/YztFEyUA48et0yTt@iweiny-mobl/ Suggested-by: Fabio M. De Francesco <fmdefrancesco@gmail.com> Suggested-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Signed-off-by: Zhao Liu <zhao1.liu@intel.com> Link: https://lore.kernel.org/r/20221020083820.2341088-1-zhao1.liu@linux.intel.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2022-10-03x86/hyperv: Replace kmap() with kmap_local_page()Zhao Liu1-2/+2
kmap() is being deprecated in favor of kmap_local_page()[1]. There are two main problems with kmap(): (1) It comes with an overhead as mapping space is restricted and protected by a global lock for synchronization and (2) it also requires global TLB invalidation when the kmap's pool wraps and it might block when the mapping space is fully utilized until a slot becomes available. With kmap_local_page() the mappings are per thread, CPU local, can take page faults, and can be called from any context (including interrupts). It is faster than kmap() in kernels with HIGHMEM enabled. Furthermore, the tasks can be preempted and, when they are scheduled to run again, the kernel virtual addresses are restored and are still valid. In the fuction hyperv_init() of hyperv/hv_init.c, the mapping is used in a single thread and is short live. So, in this case, it's safe to simply use kmap_local_page() to create mapping, and this avoids the wasted cost of kmap() for global synchronization. In addtion, the fuction hyperv_init() checks if kmap() fails by BUG_ON(). From the original discussion[2], the BUG_ON() here is just used to explicitly panic NULL pointer. So still keep the BUG_ON() in place to check if kmap_local_page() fails. Based on this consideration, memcpy_to_page() is not selected here but only kmap_local_page() is used. Therefore, replace kmap() with kmap_local_page() in hyperv/hv_init.c. [1]: https://lore.kernel.org/all/20220813220034.806698-1-ira.weiny@intel.com [2]: https://lore.kernel.org/lkml/20200915103710.cqmdvzh5lys4wsqo@liuwe-devbox-debian-v2/ Suggested-by: Dave Hansen <dave.hansen@intel.com> Suggested-by: Ira Weiny <ira.weiny@intel.com> Suggested-by: Fabio M. De Francesco <fmdefrancesco@gmail.com> Signed-off-by: Zhao Liu <zhao1.liu@intel.com> Link: https://lore.kernel.org/r/20220928095640.626350-1-zhao1.liu@linux.intel.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2022-09-28hyperv: simplify and rename generate_guest_idLi kunyu1-1/+1
The generate_guest_id function is more suitable for use after the following modifications. 1. The return value of the function is modified to u64. 2. Remove the d_info1 and d_info2 parameters from the function, keep the u64 type kernel_version parameter. 3. Rename the function to make it clearly a Hyper-V related function, and modify it to hv_generate_guest_id. Signed-off-by: Li kunyu <kunyu@nfschina.com> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Link: https://lore.kernel.org/r/20220928064046.3545-1-kunyu@nfschina.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2022-08-05Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds1-1/+1
Pull kvm updates from Paolo Bonzini: "Quite a large pull request due to a selftest API overhaul and some patches that had come in too late for 5.19. ARM: - Unwinder implementations for both nVHE modes (classic and protected), complete with an overflow stack - Rework of the sysreg access from userspace, with a complete rewrite of the vgic-v3 view to allign with the rest of the infrastructure - Disagregation of the vcpu flags in separate sets to better track their use model. - A fix for the GICv2-on-v3 selftest - A small set of cosmetic fixes RISC-V: - Track ISA extensions used by Guest using bitmap - Added system instruction emulation framework - Added CSR emulation framework - Added gfp_custom flag in struct kvm_mmu_memory_cache - Added G-stage ioremap() and iounmap() functions - Added support for Svpbmt inside Guest s390: - add an interface to provide a hypervisor dump for secure guests - improve selftests to use TAP interface - enable interpretive execution of zPCI instructions (for PCI passthrough) - First part of deferred teardown - CPU Topology - PV attestation - Minor fixes x86: - Permit guests to ignore single-bit ECC errors - Intel IPI virtualization - Allow getting/setting pending triple fault with KVM_GET/SET_VCPU_EVENTS - PEBS virtualization - Simplify PMU emulation by just using PERF_TYPE_RAW events - More accurate event reinjection on SVM (avoid retrying instructions) - Allow getting/setting the state of the speaker port data bit - Refuse starting the kvm-intel module if VM-Entry/VM-Exit controls are inconsistent - "Notify" VM exit (detect microarchitectural hangs) for Intel - Use try_cmpxchg64 instead of cmpxchg64 - Ignore benign host accesses to PMU MSRs when PMU is disabled - Allow disabling KVM's "MONITOR/MWAIT are NOPs!" behavior - Allow NX huge page mitigation to be disabled on a per-vm basis - Port eager page splitting to shadow MMU as well - Enable CMCI capability by default and handle injected UCNA errors - Expose pid of vcpu threads in debugfs - x2AVIC support for AMD - cleanup PIO emulation - Fixes for LLDT/LTR emulation - Don't require refcounted "struct page" to create huge SPTEs - Miscellaneous cleanups: - MCE MSR emulation - Use separate namespaces for guest PTEs and shadow PTEs bitmasks - PIO emulation - Reorganize rmap API, mostly around rmap destruction - Do not workaround very old KVM bugs for L0 that runs with nesting enabled - new selftests API for CPUID Generic: - Fix races in gfn->pfn cache refresh; do not pin pages tracked by the cache - new selftests API using struct kvm_vcpu instead of a (vm, id) tuple" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (606 commits) selftests: kvm: set rax before vmcall selftests: KVM: Add exponent check for boolean stats selftests: KVM: Provide descriptive assertions in kvm_binary_stats_test selftests: KVM: Check stat name before other fields KVM: x86/mmu: remove unused variable RISC-V: KVM: Add support for Svpbmt inside Guest/VM RISC-V: KVM: Use PAGE_KERNEL_IO in kvm_riscv_gstage_ioremap() RISC-V: KVM: Add G-stage ioremap() and iounmap() functions KVM: Add gfp_custom flag in struct kvm_mmu_memory_cache RISC-V: KVM: Add extensible CSR emulation framework RISC-V: KVM: Add extensible system instruction emulation framework RISC-V: KVM: Factor-out instruction emulation into separate sources RISC-V: KVM: move preempt_disable() call in kvm_arch_vcpu_ioctl_run RISC-V: KVM: Make kvm_riscv_guest_timer_init a void function RISC-V: KVM: Fix variable spelling mistake RISC-V: KVM: Improve ISA extension by using a bitmap KVM, x86/mmu: Fix the comment around kvm_tdp_mmu_zap_leafs() KVM: SVM: Dump Virtual Machine Save Area (VMSA) to klog KVM: x86/mmu: Treat NX as a valid SPTE bit for NPT KVM: x86: Do not block APIC write for non ICR registers ...
2022-08-01Merge remote-tracking branch 'kvm/next' into kvm-next-5.20Paolo Bonzini1-1/+1
KVM/s390, KVM/x86 and common infrastructure changes for 5.20 x86: * Permit guests to ignore single-bit ECC errors * Fix races in gfn->pfn cache refresh; do not pin pages tracked by the cache * Intel IPI virtualization * Allow getting/setting pending triple fault with KVM_GET/SET_VCPU_EVENTS * PEBS virtualization * Simplify PMU emulation by just using PERF_TYPE_RAW events * More accurate event reinjection on SVM (avoid retrying instructions) * Allow getting/setting the state of the speaker port data bit * Refuse starting the kvm-intel module if VM-Entry/VM-Exit controls are inconsistent * "Notify" VM exit (detect microarchitectural hangs) for Intel * Cleanups for MCE MSR emulation s390: * add an interface to provide a hypervisor dump for secure guests * improve selftests to use TAP interface * enable interpretive execution of zPCI instructions (for PCI passthrough) * First part of deferred teardown * CPU Topology * PV attestation * Minor fixes Generic: * new selftests API using struct kvm_vcpu instead of a (vm, id) tuple x86: * Use try_cmpxchg64 instead of cmpxchg64 * Bugfixes * Ignore benign host accesses to PMU MSRs when PMU is disabled * Allow disabling KVM's "MONITOR/MWAIT are NOPs!" behavior * x86/MMU: Allow NX huge pages to be disabled on a per-vm basis * Port eager page splitting to shadow MMU as well * Enable CMCI capability by default and handle injected UCNA errors * Expose pid of vcpu threads in debugfs * x2AVIC support for AMD * cleanup PIO emulation * Fixes for LLDT/LTR emulation * Don't require refcounted "struct page" to create huge SPTEs x86 cleanups: * Use separate namespaces for guest PTEs and shadow PTEs bitmasks * PIO emulation * Reorganize rmap API, mostly around rmap destruction * Do not workaround very old KVM bugs for L0 that runs with nesting enabled * new selftests API for CPUID
2022-07-07genirq: Return a const cpumask from irq_data_get_affinity_maskSamuel Holland1-1/+1
Now that the irq_data_update_affinity helper exists, enforce its use by returning a a const cpumask from irq_data_get_affinity_mask. Since the previous commit already updated places that needed to call irq_data_update_affinity, this commit updates the remaining code that either did not modify the cpumask or immediately passed the modified mask to irq_set_affinity. Signed-off-by: Samuel Holland <samuel@sholland.org> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220701200056.46555-8-samuel@sholland.org
2022-06-24KVM: x86: lapic: Rename [GET/SET]_APIC_DEST_FIELD to [GET/SET]_XAPIC_DEST_FIELDSuravee Suthikulpanit1-1/+1
To signify that the macros only support 8-bit xAPIC destination ID. Suggested-by: Maxim Levitsky <mlevitsk@redhat.com> Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Reviewed-by: Pankaj Gupta <pankaj.gupta@amd.com> Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <20220519102709.24125-3-suravee.suthikulpanit@amd.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-06-15x86/Hyper-V: Add SEV negotiate protocol support in Isolation VMTianyu Lan2-6/+84
Hyper-V Isolation VM current code uses sev_es_ghcb_hv_call() to read/write MSR via GHCB page and depends on the sev code. This may cause regression when sev code changes interface design. The latest SEV-ES code requires to negotiate GHCB version before reading/writing MSR via GHCB page and sev_es_ghcb_hv_call() doesn't work for Hyper-V Isolation VM. Add Hyper-V ghcb related implementation to decouple SEV and Hyper-V code. Negotiate GHCB version in the hyperv_init() and use the version to communicate with Hyper-V in the ghcb hv call function. Fixes: 2ea29c5abbc2 ("x86/sev: Save the negotiated GHCB version") Signed-off-by: Tianyu Lan <Tianyu.Lan@microsoft.com> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Link: https://lore.kernel.org/r/20220614014553.1915929-1-ltykernel@gmail.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2022-01-16Merge tag 'hyperv-next-signed-20220114' of ↵Linus Torvalds3-11/+50
git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux Pull hyperv updates from Wei Liu: - More patches for Hyper-V isolation VM support (Tianyu Lan) - Bug fixes and clean-up patches from various people * tag 'hyperv-next-signed-20220114' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux: scsi: storvsc: Fix storvsc_queuecommand() memory leak x86/hyperv: Properly deal with empty cpumasks in hyperv_flush_tlb_multi() Drivers: hv: vmbus: Initialize request offers message for Isolation VM scsi: storvsc: Fix unsigned comparison to zero swiotlb: Add CONFIG_HAS_IOMEM check around swiotlb_mem_remap() x86/hyperv: Fix definition of hv_ghcb_pg variable Drivers: hv: Fix definition of hypercall input & output arg variables net: netvsc: Add Isolation VM support for netvsc driver scsi: storvsc: Add Isolation VM support for storvsc driver hyper-v: Enable swiotlb bounce buffer for Isolation VM x86/hyper-v: Add hyperv Isolation VM check in the cc_platform_has() swiotlb: Add swiotlb bounce buffer remap function for HV IVM
2022-01-10x86/hyperv: Properly deal with empty cpumasks in hyperv_flush_tlb_multi()Vitaly Kuznetsov1-10/+9
KASAN detected the following issue: BUG: KASAN: slab-out-of-bounds in hyperv_flush_tlb_multi+0xf88/0x1060 Read of size 4 at addr ffff8880011ccbc0 by task kcompactd0/33 CPU: 1 PID: 33 Comm: kcompactd0 Not tainted 5.14.0-39.el9.x86_64+debug #1 Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v4.0 12/17/2019 Call Trace: dump_stack_lvl+0x57/0x7d print_address_description.constprop.0+0x1f/0x140 ? hyperv_flush_tlb_multi+0xf88/0x1060 __kasan_report.cold+0x7f/0x11e ? hyperv_flush_tlb_multi+0xf88/0x1060 kasan_report+0x38/0x50 hyperv_flush_tlb_multi+0xf88/0x1060 flush_tlb_mm_range+0x1b1/0x200 ptep_clear_flush+0x10e/0x150 ... Allocated by task 0: kasan_save_stack+0x1b/0x40 __kasan_kmalloc+0x7c/0x90 hv_common_init+0xae/0x115 hyperv_init+0x97/0x501 apic_intr_mode_init+0xb3/0x1e0 x86_late_time_init+0x92/0xa2 start_kernel+0x338/0x3eb secondary_startup_64_no_verify+0xc2/0xcb The buggy address belongs to the object at ffff8880011cc800 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 960 bytes inside of 1024-byte region [ffff8880011cc800, ffff8880011ccc00) 'hyperv_flush_tlb_multi+0xf88/0x1060' points to hv_cpu_number_to_vp_number() and '960 bytes' means we're trying to get VP_INDEX for CPU#240. 'nr_cpus' here is exactly 240 so we're trying to access past hv_vp_index's last element. This can (and will) happen when 'cpus' mask is empty and cpumask_last() will return '>=nr_cpus'. Commit ad0a6bad4475 ("x86/hyperv: check cpu mask after interrupt has been disabled") tried to deal with empty cpumask situation but apparently didn't fully fix the issue. 'cpus' cpumask which is passed to hyperv_flush_tlb_multi() is 'mm_cpumask(mm)' (which is '&mm->cpu_bitmap'). This mask changes every time the particular mm is scheduled/unscheduled on some CPU (see switch_mm_irqs_off()), disabling IRQs on the CPU which is performing remote TLB flush has zero influence on whether the particular process can get scheduled/unscheduled on _other_ CPUs so e.g. in the case where the mm was scheduled on one other CPU and got unscheduled during hyperv_flush_tlb_multi()'s execution will lead to cpumask becoming empty. It doesn't seem that there's a good way to protect 'mm_cpumask(mm)' from changing during hyperv_flush_tlb_multi()'s execution. It would be possible to copy it in the very beginning of the function but this is a waste. It seems we can deal with changing cpumask just fine. When 'cpus' cpumask changes during hyperv_flush_tlb_multi()'s execution, there are two possible issues: - 'Under-flushing': we will not flush TLB on a CPU which got added to the mask while hyperv_flush_tlb_multi() was already running. This is not a problem as this is equal to mm getting scheduled on that CPU right after TLB flush. - 'Over-flushing': we may flush TLB on a CPU which is already cleared from the mask. First, extra TLB flush preserves correctness. Second, Hyper-V's TLB flush hypercall takes 'mm->pgd' argument so Hyper-V may avoid the flush if CR3 doesn't match. Fix the immediate issue with cpumask_last()/hv_cpu_number_to_vp_number() and remove the pointless cpumask_empty() check from the beginning of the function as it really doesn't protect anything. Also, avoid the hypercall altogether when 'flush->processor_mask' ends up being empty. Fixes: ad0a6bad4475 ("x86/hyperv: check cpu mask after interrupt has been disabled") Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Link: https://lore.kernel.org/r/20220106094611.1404218-1-vkuznets@redhat.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2021-12-28x86/hyperv: Fix definition of hv_ghcb_pg variableMichael Kelley1-1/+1
The percpu variable hv_ghcb_pg is incorrectly defined. The __percpu qualifier should be associated with the union hv_ghcb * (i.e., a pointer), not with the target of the pointer. This distinction makes no difference to gcc and the generated code, but sparse correctly complains. Fix the definition in the interest of general correctness in addition to making sparse happy. No functional change. Fixes: 0cc4f6d9f0b9 ("x86/hyperv: Initialize GHCB page in Isolation VM") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Michael Kelley <mikelley@microsoft.com> Link: https://lore.kernel.org/r/1640662315-22260-2-git-send-email-mikelley@microsoft.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2021-12-20net: netvsc: Add Isolation VM support for netvsc driverTianyu Lan1-0/+28
In Isolation VM, all shared memory with host needs to mark visible to host via hvcall. vmbus_establish_gpadl() has already done it for netvsc rx/tx ring buffer. The page buffer used by vmbus_sendpacket_ pagebuffer() stills need to be handled. Use DMA API to map/umap these memory during sending/receiving packet and Hyper-V swiotlb bounce buffer dma address will be returned. The swiotlb bounce buffer has been masked to be visible to host during boot up. rx/tx ring buffer is allocated via vzalloc() and they need to be mapped into unencrypted address space(above vTOM) before sharing with host and accessing. Add hv_map/unmap_memory() to map/umap rx /tx ring buffer. Signed-off-by: Tianyu Lan <Tianyu.Lan@microsoft.com> Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Link: https://lore.kernel.org/r/20211213071407.314309-6-ltykernel@gmail.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2021-12-20hyper-v: Enable swiotlb bounce buffer for Isolation VMTianyu Lan1-0/+12
hyperv Isolation VM requires bounce buffer support to copy data from/to encrypted memory and so enable swiotlb force mode to use swiotlb bounce buffer for DMA transaction. In Isolation VM with AMD SEV, the bounce buffer needs to be accessed via extra address space which is above shared_gpa_boundary (E.G 39 bit address line) reported by Hyper-V CPUID ISOLATION_CONFIG. The access physical address will be original physical address + shared_gpa_boundary. The shared_gpa_boundary in the AMD SEV SNP spec is called virtual top of memory(vTOM). Memory addresses below vTOM are automatically treated as private while memory above vTOM is treated as shared. Swiotlb bounce buffer code calls set_memory_decrypted() to mark bounce buffer visible to host and map it in extra address space via memremap. Populate the shared_gpa_boundary (vTOM) via swiotlb_unencrypted_base variable. The map function memremap() can't work in the early place (e.g ms_hyperv_init_platform()) and so call swiotlb_update_mem_ attributes() in the hyperv_init(). Signed-off-by: Tianyu Lan <Tianyu.Lan@microsoft.com> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Link: https://lore.kernel.org/r/20211213071407.314309-4-ltykernel@gmail.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2021-12-09x86/hyperv: Refactor hv_msi_domain_free_irqs()Thomas Gleixner1-38/+17
No point in looking up things over and over. Just look up the associated irq data and work from there. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Acked-by: Wei Liu <wei.liu@kernel.org> Link: https://lore.kernel.org/r/20211206210224.429625690@linutronix.de
2021-11-15x86/hyperv: Move required MSRs check to initial platform probingSean Christopherson1-8/+1
Explicitly check for MSR_HYPERCALL and MSR_VP_INDEX support when probing for running as a Hyper-V guest instead of waiting until hyperv_init() to detect the bogus configuration. Add messages to give the admin a heads up that they are likely running on a broken virtual machine setup. At best, silently disabling Hyper-V is confusing and difficult to debug, e.g. the kernel _says_ it's using all these fancy Hyper-V features, but always falls back to the native versions. At worst, the half baked setup will crash/hang the kernel. Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Link: https://lore.kernel.org/r/20211104182239.1302956-3-seanjc@google.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2021-11-15x86/hyperv: Fix NULL deref in set_hv_tscchange_cb() if Hyper-V setup failsSean Christopherson1-0/+3
Check for a valid hv_vp_index array prior to derefencing hv_vp_index when setting Hyper-V's TSC change callback. If Hyper-V setup failed in hyperv_init(), the kernel will still report that it's running under Hyper-V, but will have silently disabled nearly all functionality. BUG: kernel NULL pointer dereference, address: 0000000000000010 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] SMP CPU: 4 PID: 1 Comm: swapper/0 Not tainted 5.15.0-rc2+ #75 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 RIP: 0010:set_hv_tscchange_cb+0x15/0xa0 Code: <8b> 04 82 8b 15 12 17 85 01 48 c1 e0 20 48 0d ee 00 01 00 f6 c6 08 ... Call Trace: kvm_arch_init+0x17c/0x280 kvm_init+0x31/0x330 vmx_init+0xba/0x13a do_one_initcall+0x41/0x1c0 kernel_init_freeable+0x1f2/0x23b kernel_init+0x16/0x120 ret_from_fork+0x22/0x30 Fixes: 93286261de1b ("x86/hyperv: Reenlightenment notifications support") Cc: stable@vger.kernel.org Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com> Link: https://lore.kernel.org/r/20211104182239.1302956-2-seanjc@google.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2021-10-28x86/hyperv: Protect set_hv_tscchange_cb() against getting preemptedVitaly Kuznetsov1-1/+4
The following issue is observed with CONFIG_DEBUG_PREEMPT when KVM loads: KVM: vmx: using Hyper-V Enlightened VMCS BUG: using smp_processor_id() in preemptible [00000000] code: systemd-udevd/488 caller is set_hv_tscchange_cb+0x16/0x80 CPU: 1 PID: 488 Comm: systemd-udevd Not tainted 5.15.0-rc5+ #396 Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v4.0 12/17/2019 Call Trace: dump_stack_lvl+0x6a/0x9a check_preemption_disabled+0xde/0xe0 ? kvm_gen_update_masterclock+0xd0/0xd0 [kvm] set_hv_tscchange_cb+0x16/0x80 kvm_arch_init+0x23f/0x290 [kvm] kvm_init+0x30/0x310 [kvm] vmx_init+0xaf/0x134 [kvm_intel] ... set_hv_tscchange_cb() can get preempted in between acquiring smp_processor_id() and writing to HV_X64_MSR_REENLIGHTENMENT_CONTROL. This is not an issue by itself: HV_X64_MSR_REENLIGHTENMENT_CONTROL is a partition-wide MSR and it doesn't matter which particular CPU will be used to receive reenlightenment notifications. The only real problem can (in theory) be observed if the CPU whose id was acquired with smp_processor_id() goes offline before we manage to write to the MSR, the logic in hv_cpu_die() won't be able to reassign it correctly. Reported-by: Michael Kelley <mikelley@microsoft.com> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Link: https://lore.kernel.org/r/20211012155005.1613352-1-vkuznets@redhat.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2021-10-28x86/hyperv: Remove duplicate includeJiapeng Chong1-2/+0
Clean up the following includecheck warning: ./arch/x86/hyperv/ivm.c: linux/bitfield.h is included more than once. ./arch/x86/hyperv/ivm.c: linux/types.h is included more than once. Reported-by: Abaci Robot <abaci@linux.alibaba.com> Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com> Link: https://lore.kernel.org/r/1635325022-99889-1-git-send-email-jiapeng.chong@linux.alibaba.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2021-10-28x86/hyperv: Remove duplicated include in hv_initWan Jiabing1-1/+0
Fix following checkinclude.pl warning: ./arch/x86/hyperv/hv_init.c: linux/io.h is included more than once. The include is in line 13. Remove the duplicated here. Signed-off-by: Wan Jiabing <wanjiabing@vivo.com> Link: https://lore.kernel.org/r/20211026113249.30481-1-wanjiabing@vivo.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2021-10-28x86/hyperv: Add ghcb hvcall support for SNP VMTianyu Lan1-0/+75
hyperv provides ghcb hvcall to handle VMBus HVCALL_SIGNAL_EVENT and HVCALL_POST_MESSAGE msg in SNP Isolation VM. Add such support. Reviewed-by: Michael Kelley <mikelley@microsoft.com> Signed-off-by: Tianyu Lan <Tianyu.Lan@microsoft.com> Link: https://lore.kernel.org/r/20211025122116.264793-8-ltykernel@gmail.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2021-10-28x86/hyperv: Add Write/Read MSR registers via ghcb pageTianyu Lan2-29/+118
Hyperv provides GHCB protocol to write Synthetic Interrupt Controller MSR registers in Isolation VM with AMD SEV SNP and these registers are emulated by hypervisor directly. Hyperv requires to write SINTx MSR registers twice. First writes MSR via GHCB page to communicate with hypervisor and then writes wrmsr instruction to talk with paravisor which runs in VMPL0. Guest OS ID MSR also needs to be set via GHCB page. Reviewed-by: Michael Kelley <mikelley@microsoft.com> Signed-off-by: Tianyu Lan <Tianyu.Lan@microsoft.com> Link: https://lore.kernel.org/r/20211025122116.264793-7-ltykernel@gmail.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2021-10-28x86/hyperv: Add new hvcall guest address host visibility supportTianyu Lan3-1/+112
Add new hvcall guest address host visibility support to mark memory visible to host. Call it inside set_memory_decrypted /encrypted(). Add HYPERVISOR feature check in the hv_is_isolation_supported() to optimize in non-virtualization environment. Acked-by: Dave Hansen <dave.hansen@intel.com> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Signed-off-by: Tianyu Lan <Tianyu.Lan@microsoft.com> Link: https://lore.kernel.org/r/20211025122116.264793-4-ltykernel@gmail.com [ wei: fix conflicts with tip ] Signed-off-by: Wei Liu <wei.liu@kernel.org>
2021-10-28x86/hyperv: Initialize GHCB page in Isolation VMTianyu Lan1-7/+61
Hyperv exposes GHCB page via SEV ES GHCB MSR for SNP guest to communicate with hypervisor. Map GHCB page for all cpus to read/write MSR register and submit hvcall request via ghcb page. Reviewed-by: Michael Kelley <mikelley@microsoft.com> Signed-off-by: Tianyu Lan <Tianyu.Lan@microsoft.com> Link: https://lore.kernel.org/r/20211025122116.264793-2-ltykernel@gmail.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2021-10-07Merge tag 'hyperv-fixes-signed-20211007' of ↵Linus Torvalds1-5/+15
git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux Pull hyperv fixes from Wei Liu: - Replace uuid.h with types.h in a header (Andy Shevchenko) - Avoid sleeping in atomic context in PCI driver (Long Li) - Avoid sending IPI to self when it shouldn't (Vitaly Kuznetsov) * tag 'hyperv-fixes-signed-20211007' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux: x86/hyperv: Avoid erroneously sending IPI to 'self' hyper-v: Replace uuid.h with types.h PCI: hv: Fix sleep while in non-sleep context when removing child devices from the bus
2021-10-06x86/hyperv: Avoid erroneously sending IPI to 'self'Vitaly Kuznetsov1-5/+15
__send_ipi_mask_ex() uses an optimization: when the target CPU mask is equal to 'cpu_present_mask' it uses 'HV_GENERIC_SET_ALL' format to avoid converting the specified cpumask to VP_SET. This case was overlooked when 'exclude_self' parameter was added. As the result, a spurious IPI to 'self' can be send. Reported-by: Thomas Gleixner <tglx@linutronix.de> Fixes: dfb5c1e12c28 ("x86/hyperv: remove on-stack cpumask from hv_send_ipi_mask_allbutself") Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Link: https://lore.kernel.org/r/20211006125016.941616-1-vkuznets@redhat.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2021-09-16Merge tag 'hyperv-fixes-signed-20210915' of ↵Linus Torvalds1-17/+26
git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux Pull hyperv fixes from Wei Liu: - Fix kernel crash caused by uio driver (Vitaly Kuznetsov) - Remove on-stack cpumask from HV APIC code (Wei Liu) * tag 'hyperv-fixes-signed-20210915' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux: x86/hyperv: remove on-stack cpumask from hv_send_ipi_mask_allbutself asm-generic/hyperv: provide cpumask_to_vpset_noself Drivers: hv: vmbus: Fix kernel crash upon unbinding a device from uio_hv_generic driver