summaryrefslogtreecommitdiff
path: root/arch/x86/hyperv/ivm.c
AgeCommit message (Collapse)Author
2024-06-17x86/mm: Make x86_platform.guest.enc_status_change_*() return an errorKirill A. Shutemov
TDX is going to have more than one reason to fail enc_status_change_prepare(). Change the callback to return errno instead of assuming -EIO. Change enc_status_change_finish() too to keep the interface symmetric. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Dave Hansen <dave.hansen@intel.com> Reviewed-by: Kai Huang <kai.huang@intel.com> Reviewed-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Tao Liu <ltao@redhat.com> Link: https://lore.kernel.org/r/20240614095904.1345461-8-kirill.shutemov@linux.intel.com
2024-03-01x86/hyperv: Make encrypted/decrypted changes safe for load_unaligned_zeropad()Michael Kelley
In a CoCo VM, when transitioning memory from encrypted to decrypted, or vice versa, the caller of set_memory_encrypted() or set_memory_decrypted() is responsible for ensuring the memory isn't in use and isn't referenced while the transition is in progress. The transition has multiple steps, and the memory is in an inconsistent state until all steps are complete. A reference while the state is inconsistent could result in an exception that can't be cleanly fixed up. However, the kernel load_unaligned_zeropad() mechanism could cause a stray reference that can't be prevented by the caller of set_memory_encrypted() or set_memory_decrypted(), so there's specific code to handle this case. But a CoCo VM running on Hyper-V may be configured to run with a paravisor, with the #VC or #VE exception routed to the paravisor. There's no architectural way to forward the exceptions back to the guest kernel, and in such a case, the load_unaligned_zeropad() specific code doesn't work. To avoid this problem, mark pages as "not present" while a transition is in progress. If load_unaligned_zeropad() causes a stray reference, a normal page fault is generated instead of #VC or #VE, and the page-fault-based fixup handlers for load_unaligned_zeropad() resolve the reference. When the encrypted/decrypted transition is complete, mark the pages as "present" again. Signed-off-by: Michael Kelley <mhklinux@outlook.com> Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com> Link: https://lore.kernel.org/r/20240116022008.1023398-4-mhklinux@outlook.com Signed-off-by: Wei Liu <wei.liu@kernel.org> Message-ID: <20240116022008.1023398-4-mhklinux@outlook.com>
2024-03-01x86/hyperv: Use slow_virt_to_phys() in page transition hypervisor callbackMichael Kelley
In preparation for temporarily marking pages not present during a transition between encrypted and decrypted, use slow_virt_to_phys() in the hypervisor callback. As long as the PFN is correct, slow_virt_to_phys() works even if the leaf PTE is not present. The existing functions that depend on vmalloc_to_page() all require that the leaf PTE be marked present, so they don't work. Update the comments for slow_virt_to_phys() to note this broader usage and the requirement to work even if the PTE is not marked present. Signed-off-by: Michael Kelley <mhklinux@outlook.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reviewed-by: Rick Edgecombe <rick.p.edgecombe@intel.com> Link: https://lore.kernel.org/r/20240116022008.1023398-2-mhklinux@outlook.com Signed-off-by: Wei Liu <wei.liu@kernel.org> Message-ID: <20240116022008.1023398-2-mhklinux@outlook.com>
2024-01-03arch/x86: Fix typosBjorn Helgaas
Fix typos, most reported by "codespell arch/x86". Only touches comments, no code changes. Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Link: https://lore.kernel.org/r/20240103004011.1758650-1-helgaas@kernel.org
2023-11-01Merge tag 'x86_tdx_for_6.7' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 TDX updates from Dave Hansen: "The majority of this is a rework of the assembly and C wrappers that are used to talk to the TDX module and VMM. This is a nice cleanup in general but is also clearing the way for using this code when Linux is the TDX VMM. There are also some tidbits to make TDX guests play nicer with Hyper-V and to take advantage the hardware TSC. Summary: - Refactor and clean up TDX hypercall/module call infrastructure - Handle retrying/resuming page conversion hypercalls - Make sure to use the (shockingly) reliable TSC in TDX guests" [ TLA reminder: TDX is "Trust Domain Extensions", Intel's guest VM confidentiality technology ] * tag 'x86_tdx_for_6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/tdx: Mark TSC reliable x86/tdx: Fix __noreturn build warning around __tdx_hypercall_failed() x86/virt/tdx: Make TDX_MODULE_CALL handle SEAMCALL #UD and #GP x86/virt/tdx: Wire up basic SEAMCALL functions x86/tdx: Remove 'struct tdx_hypercall_args' x86/tdx: Reimplement __tdx_hypercall() using TDX_MODULE_CALL asm x86/tdx: Make TDX_HYPERCALL asm similar to TDX_MODULE_CALL x86/tdx: Extend TDX_MODULE_CALL to support more TDCALL/SEAMCALL leafs x86/tdx: Pass TDCALL/SEAMCALL input/output registers via a structure x86/tdx: Rename __tdx_module_call() to __tdcall() x86/tdx: Make macros of TDCALLs consistent with the spec x86/tdx: Skip saving output regs when SEAMCALL fails with VMFailInvalid x86/tdx: Zero out the missing RSI in TDX_HYPERCALL macro x86/tdx: Retry partially-completed page conversion hypercalls
2023-10-13x86/apic, x86/hyperv: Use u32 in hv_snp_boot_ap() tooIngo Molnar
The data type for APIC IDs was standardized to 'u32' in the following recent commit: db4a4086a223 ("x86/apic: Use u32 for wakeup_secondary_cpu[_64]()") Which changed the function arguments type signature of the apic->wakeup_secondary_cpu() APIC driver function. Propagate this to hv_snp_boot_ap() as well, which also addresses a 'assignment from incompatible pointer type' build warning that triggers under the -Werror=incompatible-pointer-types GCC warning. Fixes: db4a4086a223 ("x86/apic: Use u32 for wakeup_secondary_cpu[_64]()") Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20230814085113.233274223@linutronix.de
2023-09-12x86/tdx: Remove 'struct tdx_hypercall_args'Kai Huang
Now 'struct tdx_hypercall_args' is basically 'struct tdx_module_args' minus RCX. Although from __tdx_hypercall()'s perspective RCX isn't used as shared register thus not part of input/output registers, it's not worth to have a separate structure just due to one register. Remove the 'struct tdx_hypercall_args' and use 'struct tdx_module_args' instead in __tdx_hypercall() related code. This also saves the memory copy between the two structures within __tdx_hypercall(). Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Kai Huang <kai.huang@intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/all/798dad5ce24e9d745cf0e16825b75ccc433ad065.1692096753.git.kai.huang%40intel.com
2023-09-12x86/tdx: Make TDX_HYPERCALL asm similar to TDX_MODULE_CALLKai Huang
Now the 'struct tdx_hypercall_args' and 'struct tdx_module_args' are almost the same, and the TDX_HYPERCALL and TDX_MODULE_CALL asm macro share similar code pattern too. The __tdx_hypercall() and __tdcall() should be unified to use the same assembly code. As a preparation to unify them, simplify the TDX_HYPERCALL to make it more like the TDX_MODULE_CALL. The TDX_HYPERCALL takes the pointer of 'struct tdx_hypercall_args' as function call argument, and does below extra things comparing to the TDX_MODULE_CALL: 1) It sets RAX to 0 (TDG.VP.VMCALL leaf) internally; 2) It sets RCX to the (fixed) bitmap of shared registers internally; 3) It calls __tdx_hypercall_failed() internally (and panics) when the TDCALL instruction itself fails; 4) After TDCALL, it moves R10 to RAX to return the return code of the VMCALL leaf, regardless the '\ret' asm macro argument; Firstly, change the TDX_HYPERCALL to take the same function call arguments as the TDX_MODULE_CALL does: TDCALL leaf ID, and the pointer to 'struct tdx_module_args'. Then 1) and 2) can be moved to the caller: - TDG.VP.VMCALL leaf ID can be passed via the function call argument; - 'struct tdx_module_args' is 'struct tdx_hypercall_args' + RCX, thus the bitmap of shared registers can be passed via RCX in the structure. Secondly, to move 3) and 4) out of assembly, make the TDX_HYPERCALL always save output registers to the structure. The caller then can: - Call __tdx_hypercall_failed() when TDX_HYPERCALL returns error; - Return R10 in the structure as the return code of the VMCALL leaf; With above changes, change the asm function from __tdx_hypercall() to __tdcall_hypercall(), and reimplement __tdx_hypercall() as the C wrapper of it. This avoids having to add another wrapper of __tdx_hypercall() (_tdx_hypercall() is already taken). The __tdcall_hypercall() will be replaced with a __tdcall() variant using TDX_MODULE_CALL in a later commit as the final goal is to have one assembly to handle both TDCALL and TDVMCALL. Currently, the __tdx_hypercall() asm is in '.noinstr.text'. To keep this unchanged, annotate __tdx_hypercall(), which is a C function now, as 'noinstr'. Remove the __tdx_hypercall_ret() as __tdx_hypercall() already does so. Implement __tdx_hypercall() in tdx-shared.c so it can be shared with the compressed code. Opportunistically fix a checkpatch error complaining using space around parenthesis '(' and ')' while moving the bitmap of shared registers to <asm/shared/tdx.h>. [ dhansen: quash new calls of __tdx_hypercall_ret() that showed up ] Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Kai Huang <kai.huang@intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/all/0cbf25e7aee3256288045023a31f65f0cef90af4.1692096753.git.kai.huang%40intel.com
2023-09-04Merge tag 'hyperv-next-signed-20230902' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux Pull hyperv updates from Wei Liu: - Support for SEV-SNP guests on Hyper-V (Tianyu Lan) - Support for TDX guests on Hyper-V (Dexuan Cui) - Use SBRM API in Hyper-V balloon driver (Mitchell Levy) - Avoid dereferencing ACPI root object handle in VMBus driver (Maciej Szmigiero) - A few misecllaneous fixes (Jiapeng Chong, Nathan Chancellor, Saurabh Sengar) * tag 'hyperv-next-signed-20230902' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux: (24 commits) x86/hyperv: Remove duplicate include x86/hyperv: Move the code in ivm.c around to avoid unnecessary ifdef's x86/hyperv: Remove hv_isolation_type_en_snp x86/hyperv: Use TDX GHCI to access some MSRs in a TDX VM with the paravisor Drivers: hv: vmbus: Bring the post_msg_page back for TDX VMs with the paravisor x86/hyperv: Introduce a global variable hyperv_paravisor_present Drivers: hv: vmbus: Support >64 VPs for a fully enlightened TDX/SNP VM x86/hyperv: Fix serial console interrupts for fully enlightened TDX guests Drivers: hv: vmbus: Support fully enlightened TDX guests x86/hyperv: Support hypercalls for fully enlightened TDX guests x86/hyperv: Add hv_isolation_type_tdx() to detect TDX guests x86/hyperv: Fix undefined reference to isolation_type_en_snp without CONFIG_HYPERV x86/hyperv: Add missing 'inline' to hv_snp_boot_ap() stub hv: hyperv.h: Replace one-element array with flexible-array member Drivers: hv: vmbus: Don't dereference ACPI root object handle x86/hyperv: Add hyperv-specific handling for VMMCALL under SEV-ES x86/hyperv: Add smp support for SEV-SNP guest clocksource: hyper-v: Mark hyperv tsc page unencrypted in sev-snp enlightened guest x86/hyperv: Use vmmcall to implement Hyper-V hypercall in sev-snp enlightened guest drivers: hv: Mark percpu hvcall input arg page unencrypted in SEV-SNP enlightened guest ...
2023-08-25x86/hyperv: Remove duplicate includeJiapeng Chong
./arch/x86/hyperv/ivm.c: asm/sev.h is included more than once. ./arch/x86/hyperv/ivm.c: asm/coco.h is included more than once. Reported-by: Abaci Robot <abaci@linux.alibaba.com> Closes: https://bugzilla.openanolis.cn/show_bug.cgi?id=6212 Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com> Reviewed-by: Dexuan Cui <decui@microsoft.com> Signed-off-by: Wei Liu <wei.liu@kernel.org> Link: https://lore.kernel.org/r/20230824080352.98945-1-jiapeng.chong@linux.alibaba.com
2023-08-25x86/hyperv: Move the code in ivm.c around to avoid unnecessary ifdef'sDexuan Cui
Group the code this way so that we can avoid too many ifdef's: Data only used in an SNP VM with the paravisor; Functions only used in an SNP VM with the paravisor; Data only used in an SNP VM without the paravisor; Functions only used in an SNP VM without the paravisor; Functions only used in a TDX VM, with and without the paravisor; Functions used in an SNP or TDX VM, when the paravisor is present; Functions always used, even in a regular non-CoCo VM. No functional change. Signed-off-by: Dexuan Cui <decui@microsoft.com> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Reviewed-by: Tianyu Lan <tiala@microsoft.com> Signed-off-by: Wei Liu <wei.liu@kernel.org> Link: https://lore.kernel.org/r/20230824080712.30327-11-decui@microsoft.com
2023-08-25x86/hyperv: Remove hv_isolation_type_en_snpDexuan Cui
In ms_hyperv_init_platform(), do not distinguish between a SNP VM with the paravisor and a SNP VM without the paravisor. Replace hv_isolation_type_en_snp() with !ms_hyperv.paravisor_present && hv_isolation_type_snp(). The hv_isolation_type_en_snp() in drivers/hv/hv.c and drivers/hv/hv_common.c can be changed to hv_isolation_type_snp() since we know !ms_hyperv.paravisor_present is true there. Signed-off-by: Dexuan Cui <decui@microsoft.com> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Reviewed-by: Tianyu Lan <tiala@microsoft.com> Signed-off-by: Wei Liu <wei.liu@kernel.org> Link: https://lore.kernel.org/r/20230824080712.30327-10-decui@microsoft.com
2023-08-25x86/hyperv: Use TDX GHCI to access some MSRs in a TDX VM with the paravisorDexuan Cui
When the paravisor is present, a SNP VM must use GHCB to access some special MSRs, including HV_X64_MSR_GUEST_OS_ID and some SynIC MSRs. Similarly, when the paravisor is present, a TDX VM must use TDX GHCI to access the same MSRs. Implement hv_tdx_msr_write() and hv_tdx_msr_read(), and use the helper functions hv_ivm_msr_read() and hv_ivm_msr_write() to access the MSRs in a unified way for SNP/TDX VMs with the paravisor. Do not export hv_tdx_msr_write() and hv_tdx_msr_read(), because we never really used hv_ghcb_msr_write() and hv_ghcb_msr_read() in any module. Update arch/x86/include/asm/mshyperv.h so that the kernel can still build if CONFIG_AMD_MEM_ENCRYPT or CONFIG_INTEL_TDX_GUEST is not set, or neither is set. Signed-off-by: Dexuan Cui <decui@microsoft.com> Reviewed-by: Tianyu Lan <tiala@microsoft.com> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Signed-off-by: Wei Liu <wei.liu@kernel.org> Link: https://lore.kernel.org/r/20230824080712.30327-9-decui@microsoft.com
2023-08-25x86/hyperv: Introduce a global variable hyperv_paravisor_presentDexuan Cui
The new variable hyperv_paravisor_present is set only when the VM is a SNP/TDX VM with the paravisor running: see ms_hyperv_init_platform(). We introduce hyperv_paravisor_present because we can not use ms_hyperv.paravisor_present in arch/x86/include/asm/mshyperv.h: struct ms_hyperv_info is defined in include/asm-generic/mshyperv.h, which is included at the end of arch/x86/include/asm/mshyperv.h, but at the beginning of arch/x86/include/asm/mshyperv.h, we would already need to use struct ms_hyperv_info in hv_do_hypercall(). We use hyperv_paravisor_present only in include/asm-generic/mshyperv.h, and use ms_hyperv.paravisor_present elsewhere. In the future, we'll introduce a hypercall function structure for different VM types, and at boot time, the right function pointers would be written into the structure so that runtime testing of TDX vs. SNP vs. normal will be avoided and hyperv_paravisor_present will no longer be needed. Call hv_vtom_init() when it's a VBS VM or when ms_hyperv.paravisor_present is true, i.e. the VM is a SNP VM or TDX VM with the paravisor. Enhance hv_vtom_init() for a TDX VM with the paravisor. In hv_common_cpu_init(), don't decrypt the hyperv_pcpu_input_arg for a TDX VM with the paravisor, just like we don't decrypt the page for a SNP VM with the paravisor. Signed-off-by: Dexuan Cui <decui@microsoft.com> Reviewed-by: Tianyu Lan <tiala@microsoft.com> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Signed-off-by: Wei Liu <wei.liu@kernel.org> Link: https://lore.kernel.org/r/20230824080712.30327-7-decui@microsoft.com
2023-08-25x86/hyperv: Support hypercalls for fully enlightened TDX guestsDexuan Cui
A fully enlightened TDX guest on Hyper-V (i.e. without the paravisor) only uses the GHCI call rather than hv_hypercall_pg. Do not initialize hypercall_pg for such a guest. In hv_common_cpu_init(), the hyperv_pcpu_input_arg page needs to be decrypted in such a guest. Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Reviewed-by: Tianyu Lan <tiala@microsoft.com> Signed-off-by: Dexuan Cui <decui@microsoft.com> Signed-off-by: Wei Liu <wei.liu@kernel.org> Link: https://lore.kernel.org/r/20230824080712.30327-3-decui@microsoft.com
2023-08-25x86/hyperv: Add hv_isolation_type_tdx() to detect TDX guestsDexuan Cui
No logic change to SNP/VBS guests. hv_isolation_type_tdx() will be used to instruct a TDX guest on Hyper-V to do some TDX-specific operations, e.g. for a fully enlightened TDX guest (i.e. without the paravisor), hv_do_hypercall() should use __tdx_hypercall() and such a guest on Hyper-V should handle the Hyper-V Event/Message/Monitor pages specially. Reviewed-by: Michael Kelley <mikelley@microsoft.com> Reviewed-by: Tianyu Lan <tiala@microsoft.com> Signed-off-by: Dexuan Cui <decui@microsoft.com> Signed-off-by: Wei Liu <wei.liu@kernel.org> Link: https://lore.kernel.org/r/20230824080712.30327-2-decui@microsoft.com
2023-08-22x86/hyperv: Add smp support for SEV-SNP guestTianyu Lan
In the AMD SEV-SNP guest, AP needs to be started up via sev es save area and Hyper-V requires to call HVCALL_START_VP hypercall to pass the gpa of sev es save area with AP's vp index and VTL(Virtual trust level) parameters. Override wakeup_secondary_cpu_64 callback with hv_snp_boot_ap. Reviewed-by: Dexuan Cui <decui@microsoft.com> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Signed-off-by: Tianyu Lan <tiala@microsoft.com> Signed-off-by: Wei Liu <wei.liu@kernel.org> Link: https://lore.kernel.org/r/20230818102919.1318039-8-ltykernel@gmail.com
2023-08-22x86/hyperv: Add sev-snp enlightened guest static keyTianyu Lan
Introduce static key isolation_type_en_snp for enlightened sev-snp guest check. Reviewed-by: Dexuan Cui <decui@microsoft.com> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Signed-off-by: Tianyu Lan <tiala@microsoft.com> Signed-off-by: Wei Liu <wei.liu@kernel.org> Link: https://lore.kernel.org/r/20230818102919.1318039-2-ltykernel@gmail.com
2023-08-04Merge tag 'hyperv-fixes-signed-20230804' of ↵Linus Torvalds
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
2023-06-28x86/hyperv: Improve code for referencing hyperv_pcpu_input_argNischala Yelchuri
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 Torvalds
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
2023-06-01x86/hyperv: Set MTRR state when running as SEV-SNP Hyper-V guestJuergen Gross
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)
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
2023-04-28Merge tag 'objtool-core-2023-04-27' of ↵Linus Torvalds
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 ...
2023-04-17hv_netvsc: Remove second mapping of send and recv buffersMichael Kelley
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. Piccoli
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 Kelley
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 Kelley
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 Kelley
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
2022-06-15x86/Hyper-V: Add SEV negotiate protocol support in Isolation VMTianyu Lan
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>
2021-12-20net: netvsc: Add Isolation VM support for netvsc driverTianyu Lan
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>
2021-10-28x86/hyperv: Remove duplicate includeJiapeng Chong
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: Add ghcb hvcall support for SNP VMTianyu Lan
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 Lan
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 Lan
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>