From: Sean Christopherson <seanjc@google.com>
To: Brijesh Singh <brijesh.singh@amd.com>
Cc: x86@kernel.org, linux-kernel@vger.kernel.org,
kvm@vger.kernel.org, linux-efi@vger.kernel.org,
platform-driver-x86@vger.kernel.org, linux-coco@lists.linux.dev,
linux-mm@kvack.org, linux-crypto@vger.kernel.org,
Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@redhat.com>, Joerg Roedel <jroedel@suse.de>,
Tom Lendacky <thomas.lendacky@amd.com>,
"H. Peter Anvin" <hpa@zytor.com>,
Ard Biesheuvel <ardb@kernel.org>,
Paolo Bonzini <pbonzini@redhat.com>,
Vitaly Kuznetsov <vkuznets@redhat.com>,
Wanpeng Li <wanpengli@tencent.com>,
Jim Mattson <jmattson@google.com>,
Andy Lutomirski <luto@kernel.org>,
Dave Hansen <dave.hansen@linux.intel.com>,
Sergio Lopez <slp@redhat.com>, Peter Gonda <pgonda@google.com>,
Peter Zijlstra <peterz@infradead.org>,
Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>,
David Rientjes <rientjes@google.com>,
Dov Murik <dovmurik@linux.ibm.com>,
Tobin Feldman-Fitzthum <tobin@ibm.com>,
Borislav Petkov <bp@alien8.de>,
Michael Roth <michael.roth@amd.com>,
Vlastimil Babka <vbabka@suse.cz>,
tony.luck@intel.com, npmccallum@redhat.com,
brijesh.ksingh@gmail.com
Subject: Re: [PATCH Part2 RFC v4 23/40] KVM: SVM: Add KVM_SEV_SNP_LAUNCH_START command
Date: Fri, 16 Jul 2021 19:43:17 +0000 [thread overview]
Message-ID: <YPHhVZLyb795z/88@google.com> (raw)
In-Reply-To: <20210707183616.5620-24-brijesh.singh@amd.com>
On Wed, Jul 07, 2021, Brijesh Singh wrote:
> @@ -1527,6 +1530,100 @@ static int sev_receive_finish(struct kvm *kvm, struct kvm_sev_cmd *argp)
> return sev_issue_cmd(kvm, SEV_CMD_RECEIVE_FINISH, &data, &argp->error);
> }
>
> +static void *snp_context_create(struct kvm *kvm, struct kvm_sev_cmd *argp)
> +{
> + struct sev_data_snp_gctx_create data = {};
> + void *context;
> + int rc;
> +
> + /* Allocate memory for context page */
Eh, I'd drop this comment. It's quite obvious that a page is being allocated
and that it's being assigned to the context.
> + context = snp_alloc_firmware_page(GFP_KERNEL_ACCOUNT);
> + if (!context)
> + return NULL;
> +
> + data.gctx_paddr = __psp_pa(context);
> + rc = __sev_issue_cmd(argp->sev_fd, SEV_CMD_SNP_GCTX_CREATE, &data, &argp->error);
> + if (rc) {
> + snp_free_firmware_page(context);
> + return NULL;
> + }
> +
> + return context;
> +}
> +
> +static int snp_bind_asid(struct kvm *kvm, int *error)
> +{
> + struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
> + struct sev_data_snp_activate data = {};
> + int asid = sev_get_asid(kvm);
> + int ret, retry_count = 0;
> +
> + /* Activate ASID on the given context */
> + data.gctx_paddr = __psp_pa(sev->snp_context);
> + data.asid = asid;
> +again:
> + ret = sev_issue_cmd(kvm, SEV_CMD_SNP_ACTIVATE, &data, error);
> +
> + /* Check if the DF_FLUSH is required, and try again */
Please provide more info on why this may be necessary. I can see from the code
that it does a flush and retries, but I have no idea why a flush would be required
in the first place, e.g. why can't KVM guarantee that everything is in the proper
state before attempting to bind an ASID?
> + if (ret && (*error == SEV_RET_DFFLUSH_REQUIRED) && (!retry_count)) {
> + /* Guard DEACTIVATE against WBINVD/DF_FLUSH used in ASID recycling */
> + down_read(&sev_deactivate_lock);
> + wbinvd_on_all_cpus();
> + ret = snp_guest_df_flush(error);
> + up_read(&sev_deactivate_lock);
> +
> + if (ret)
> + return ret;
> +
> + /* only one retry */
Again, please explain why. Is this arbitrary? Is retrying more than once
guaranteed to be useless?
> + retry_count = 1;
> +
> + goto again;
> + }
> +
> + return ret;
> +}
...
> void sev_vm_destroy(struct kvm *kvm)
> {
> struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
> @@ -1847,7 +1969,15 @@ void sev_vm_destroy(struct kvm *kvm)
>
> mutex_unlock(&kvm->lock);
>
> - sev_unbind_asid(kvm, sev->handle);
> + if (sev_snp_guest(kvm)) {
> + if (snp_decommission_context(kvm)) {
> + pr_err("Failed to free SNP guest context, leaking asid!\n");
I agree with Peter that this likely warrants a WARN. If a WARN isn't justified,
e.g. this can happen without a KVM/CPU bug, then there absolutely needs to be a
massive comment explaining why we have code that result in memory leaks.
> + return;
> + }
> + } else {
> + sev_unbind_asid(kvm, sev->handle);
> + }
> +
> sev_asid_free(sev);
> }
>
> diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h
> index b9ea99f8579e..bc5582b44356 100644
> --- a/arch/x86/kvm/svm/svm.h
> +++ b/arch/x86/kvm/svm/svm.h
> @@ -67,6 +67,7 @@ struct kvm_sev_info {
> u64 ap_jump_table; /* SEV-ES AP Jump Table address */
> struct kvm *enc_context_owner; /* Owner of copied encryption context */
> struct misc_cg *misc_cg; /* For misc cgroup accounting */
> + void *snp_context; /* SNP guest context page */
> };
>
> struct kvm_svm {
> diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
> index 989a64aa1ae5..dbd05179d8fa 100644
> --- a/include/uapi/linux/kvm.h
> +++ b/include/uapi/linux/kvm.h
> @@ -1680,6 +1680,7 @@ enum sev_cmd_id {
>
> /* SNP specific commands */
> KVM_SEV_SNP_INIT = 256,
> + KVM_SEV_SNP_LAUNCH_START,
>
> KVM_SEV_NR_MAX,
> };
> @@ -1781,6 +1782,14 @@ struct kvm_snp_init {
> __u64 flags;
> };
>
> +struct kvm_sev_snp_launch_start {
> + __u64 policy;
> + __u64 ma_uaddr;
> + __u8 ma_en;
> + __u8 imi_en;
> + __u8 gosvw[16];
Hmm, I'd prefer to pad this out to be 8-byte sized.
> +};
> +
> #define KVM_DEV_ASSIGN_ENABLE_IOMMU (1 << 0)
> #define KVM_DEV_ASSIGN_PCI_2_3 (1 << 1)
> #define KVM_DEV_ASSIGN_MASK_INTX (1 << 2)
> --
> 2.17.1
>
next prev parent reply other threads:[~2021-07-16 19:43 UTC|newest]
Thread overview: 178+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-07-07 18:35 [PATCH Part2 RFC v4 00/40] Add AMD Secure Nested Paging (SEV-SNP) Hypervisor Support Brijesh Singh
2021-07-07 18:35 ` [PATCH Part2 RFC v4 01/40] KVM: SVM: Add support to handle AP reset MSR protocol Brijesh Singh
2021-07-14 20:17 ` Sean Christopherson
2021-07-15 7:39 ` Joerg Roedel
2021-07-15 13:42 ` Tom Lendacky
2021-07-15 15:45 ` Sean Christopherson
2021-07-15 17:05 ` Tom Lendacky
2021-07-07 18:35 ` [PATCH Part2 RFC v4 02/40] KVM: SVM: Provide the Hypervisor Feature support VMGEXIT Brijesh Singh
2021-07-14 20:37 ` Sean Christopherson
2021-07-14 21:00 ` Brijesh Singh
2021-07-07 18:35 ` [PATCH Part2 RFC v4 03/40] x86/cpufeatures: Add SEV-SNP CPU feature Brijesh Singh
2021-07-07 18:35 ` [PATCH Part2 RFC v4 04/40] x86/sev: Add the host SEV-SNP initialization support Brijesh Singh
2021-07-14 21:07 ` Sean Christopherson
2021-07-14 22:02 ` Brijesh Singh
2021-07-14 22:06 ` Sean Christopherson
2021-07-14 22:11 ` Brijesh Singh
2022-06-02 11:47 ` Jarkko Sakkinen
2022-06-06 11:42 ` Dr. David Alan Gilbert
2021-07-07 18:35 ` [PATCH Part2 RFC v4 05/40] x86/sev: Add RMP entry lookup helpers Brijesh Singh
2021-07-15 18:37 ` Sean Christopherson
2021-07-15 19:28 ` Brijesh Singh
2021-07-16 17:22 ` Brijesh Singh
2021-07-20 22:06 ` Sean Christopherson
2021-07-20 23:10 ` Brijesh Singh
2021-07-07 18:35 ` [PATCH Part2 RFC v4 06/40] x86/sev: Add helper functions for RMPUPDATE and PSMASH instruction Brijesh Singh
2021-07-12 18:44 ` Peter Gonda
2021-07-12 19:00 ` Dave Hansen
2021-07-15 18:56 ` Sean Christopherson
2021-07-15 19:08 ` Dave Hansen
2021-07-15 19:18 ` Sean Christopherson
2021-07-07 18:35 ` [PATCH Part2 RFC v4 07/40] x86/sev: Split the physmap when adding the page in RMP table Brijesh Singh
2021-07-14 22:25 ` Sean Christopherson
2021-07-15 17:05 ` Brijesh Singh
2021-07-15 17:51 ` Sean Christopherson
2021-07-15 18:14 ` Brijesh Singh
2021-07-15 18:39 ` Sean Christopherson
2021-07-15 19:38 ` Brijesh Singh
2021-07-15 22:01 ` Sean Christopherson
2021-07-15 22:11 ` Brijesh Singh
2021-07-30 11:31 ` Vlastimil Babka
2021-07-30 16:10 ` Brijesh Singh
2021-07-07 18:35 ` [PATCH Part2 RFC v4 08/40] x86/traps: Define RMP violation #PF error code Brijesh Singh
2021-07-15 19:02 ` Sean Christopherson
2021-07-15 19:16 ` Dave Hansen
2021-07-07 18:35 ` [PATCH Part2 RFC v4 09/40] x86/fault: Add support to dump RMP entry on fault Brijesh Singh
2021-07-07 19:21 ` Dave Hansen
2021-07-08 15:02 ` Brijesh Singh
2021-07-08 15:30 ` Dave Hansen
2021-07-08 16:48 ` Brijesh Singh
2021-07-08 16:58 ` Dave Hansen
2021-07-08 17:11 ` Brijesh Singh
2021-07-08 17:15 ` Dave Hansen
2021-07-07 18:35 ` [PATCH Part2 RFC v4 10/40] x86/fault: Add support to handle the RMP fault for user address Brijesh Singh
2021-07-08 16:16 ` Dave Hansen
2021-07-12 15:43 ` Brijesh Singh
2021-07-12 16:00 ` Dave Hansen
2021-07-12 16:11 ` Brijesh Singh
2021-07-12 16:15 ` Dave Hansen
2021-07-12 16:24 ` Brijesh Singh
2021-07-12 16:29 ` Dave Hansen
2021-07-12 16:49 ` Brijesh Singh
2021-07-15 21:53 ` Sean Christopherson
2021-07-30 16:00 ` Vlastimil Babka
2021-07-30 16:31 ` Dave Hansen
2021-07-07 18:35 ` [PATCH Part2 RFC v4 11/40] crypto:ccp: Define the SEV-SNP commands Brijesh Singh
2021-07-07 18:35 ` [PATCH Part2 RFC v4 12/40] crypto: ccp: Add support to initialize the AMD-SP for SEV-SNP Brijesh Singh
2021-07-07 18:35 ` [PATCH Part2 RFC v4 13/40] crypto: ccp: Shutdown SNP firmware on kexec Brijesh Singh
2021-07-07 18:35 ` [PATCH Part2 RFC v4 14/40] crypto:ccp: Provide APIs to issue SEV-SNP commands Brijesh Singh
2021-07-08 18:56 ` Dr. David Alan Gilbert
2021-07-07 18:35 ` [PATCH Part2 RFC v4 15/40] crypto: ccp: Handle the legacy TMR allocation when SNP is enabled Brijesh Singh
2021-07-14 13:22 ` Marc Orr
2021-07-14 16:45 ` Brijesh Singh
2021-07-14 18:14 ` Marc Orr
2021-07-15 23:48 ` Sean Christopherson
2021-07-16 12:55 ` Brijesh Singh
2021-07-16 15:35 ` Sean Christopherson
2021-07-16 15:47 ` Brijesh Singh
2021-07-07 18:35 ` [PATCH Part2 RFC v4 16/40] crypto: ccp: Handle the legacy SEV command " Brijesh Singh
2021-07-07 18:35 ` [PATCH Part2 RFC v4 17/40] crypto: ccp: Add the SNP_PLATFORM_STATUS command Brijesh Singh
2021-07-07 18:35 ` [PATCH Part2 RFC v4 18/40] crypto: ccp: Add the SNP_{SET,GET}_EXT_CONFIG command Brijesh Singh
2021-07-07 18:35 ` [PATCH Part2 RFC v4 19/40] crypto: ccp: provide APIs to query extended attestation report Brijesh Singh
2021-07-07 18:35 ` [PATCH Part2 RFC v4 20/40] KVM: SVM: Make AVIC backing, VMSA and VMCB memory allocation SNP safe Brijesh Singh
2021-07-14 13:35 ` Marc Orr
2021-07-14 16:47 ` Brijesh Singh
2021-07-20 18:02 ` Sean Christopherson
2021-08-03 14:38 ` Brijesh Singh
2021-07-07 18:35 ` [PATCH Part2 RFC v4 21/40] KVM: SVM: Add initial SEV-SNP support Brijesh Singh
2021-07-16 18:00 ` Sean Christopherson
2021-07-16 18:46 ` Brijesh Singh
2021-07-16 19:31 ` Sean Christopherson
2021-07-16 21:03 ` Brijesh Singh
2021-07-07 18:35 ` [PATCH Part2 RFC v4 22/40] KVM: SVM: Add KVM_SNP_INIT command Brijesh Singh
2021-07-16 19:33 ` Sean Christopherson
2021-07-16 21:25 ` Brijesh Singh
2021-07-19 20:24 ` Sean Christopherson
2021-07-07 18:35 ` [PATCH Part2 RFC v4 23/40] KVM: SVM: Add KVM_SEV_SNP_LAUNCH_START command Brijesh Singh
2021-07-12 18:45 ` Peter Gonda
2021-07-16 19:43 ` Sean Christopherson [this message]
2021-07-16 21:42 ` Brijesh Singh
2021-07-07 18:36 ` [PATCH Part2 RFC v4 24/40] KVM: SVM: Add KVM_SEV_SNP_LAUNCH_UPDATE command Brijesh Singh
2021-07-16 20:01 ` Sean Christopherson
2021-07-16 22:00 ` Brijesh Singh
2021-07-19 20:51 ` Sean Christopherson
2021-07-19 21:34 ` Brijesh Singh
2021-07-19 21:36 ` Brijesh Singh
2021-07-07 18:36 ` [PATCH Part2 RFC v4 25/40] KVM: SVM: Reclaim the guest pages when SEV-SNP VM terminates Brijesh Singh
2021-07-16 20:09 ` Sean Christopherson
2021-07-16 22:16 ` Brijesh Singh
2021-07-17 0:46 ` Sean Christopherson
2021-07-19 12:55 ` Brijesh Singh
2021-07-19 17:18 ` Sean Christopherson
2021-07-19 18:34 ` Brijesh Singh
2021-07-19 19:03 ` Sean Christopherson
2021-07-19 19:14 ` Sean Christopherson
2021-07-19 19:37 ` Brijesh Singh
2021-07-20 16:40 ` Sean Christopherson
2021-07-20 18:23 ` Brijesh Singh
2021-07-07 18:36 ` [PATCH Part2 RFC v4 26/40] KVM: SVM: Add KVM_SEV_SNP_LAUNCH_FINISH command Brijesh Singh
2021-07-16 20:18 ` Sean Christopherson
2021-07-16 22:48 ` Brijesh Singh
2021-07-19 16:54 ` Sean Christopherson
2021-07-19 18:29 ` Brijesh Singh
2021-07-19 19:14 ` Sean Christopherson
2021-07-19 19:49 ` Brijesh Singh
2021-07-19 20:13 ` Sean Christopherson
2021-07-21 17:53 ` Marc Orr
2021-07-07 18:36 ` [PATCH Part2 RFC v4 27/40] KVM: X86: Add kvm_x86_ops to get the max page level for the TDP Brijesh Singh
2021-07-16 19:19 ` Sean Christopherson
2021-07-16 20:41 ` Brijesh Singh
2021-07-20 19:38 ` Sean Christopherson
2021-07-20 20:06 ` Brijesh Singh
2021-07-07 18:36 ` [PATCH Part2 RFC v4 28/40] KVM: X86: Introduce kvm_mmu_map_tdp_page() for use by SEV Brijesh Singh
2021-07-16 18:15 ` Sean Christopherson
2021-07-07 18:36 ` [PATCH Part2 RFC v4 29/40] KVM: X86: Introduce kvm_mmu_get_tdp_walk() for SEV-SNP use Brijesh Singh
2021-07-07 18:36 ` [PATCH Part2 RFC v4 30/40] KVM: X86: Define new RMP check related #NPF error bits Brijesh Singh
2021-07-16 20:22 ` Sean Christopherson
2021-07-17 0:34 ` Brijesh Singh
2021-07-07 18:36 ` [PATCH Part2 RFC v4 31/40] KVM: X86: update page-fault trace to log the 64-bit error code Brijesh Singh
2021-07-16 20:25 ` Sean Christopherson
2021-07-17 0:35 ` Brijesh Singh
2021-07-07 18:36 ` [PATCH Part2 RFC v4 32/40] KVM: SVM: Add support to handle GHCB GPA register VMGEXIT Brijesh Singh
2021-07-16 20:45 ` Sean Christopherson
2021-07-17 0:44 ` Brijesh Singh
2021-07-19 20:04 ` Sean Christopherson
2021-07-07 18:36 ` [PATCH Part2 RFC v4 33/40] KVM: SVM: Add support to handle MSR based Page State Change VMGEXIT Brijesh Singh
2021-07-16 21:00 ` Sean Christopherson
2021-07-19 14:19 ` Brijesh Singh
2021-07-19 18:55 ` Sean Christopherson
2021-07-19 19:15 ` Brijesh Singh
2021-08-13 16:32 ` Borislav Petkov
2021-07-07 18:36 ` [PATCH Part2 RFC v4 34/40] KVM: SVM: Add support to handle " Brijesh Singh
2021-07-16 21:14 ` Sean Christopherson
2021-07-19 14:24 ` Brijesh Singh
2021-07-07 18:36 ` [PATCH Part2 RFC v4 35/40] KVM: Add arch hooks to track the host write to guest memory Brijesh Singh
2021-07-19 23:30 ` Sean Christopherson
2021-07-20 15:15 ` Brijesh Singh
2021-07-07 18:36 ` [PATCH Part2 RFC v4 36/40] KVM: X86: Export the kvm_zap_gfn_range() for the SNP use Brijesh Singh
2021-07-07 18:36 ` [PATCH Part2 RFC v4 37/40] KVM: SVM: Add support to handle the RMP nested page fault Brijesh Singh
2021-07-20 0:10 ` Sean Christopherson
2021-07-20 17:55 ` Brijesh Singh
2021-07-20 22:31 ` Sean Christopherson
2021-07-20 23:53 ` Brijesh Singh
2021-07-21 20:15 ` Sean Christopherson
2021-07-07 18:36 ` [PATCH Part2 RFC v4 38/40] KVM: SVM: Provide support for SNP_GUEST_REQUEST NAE event Brijesh Singh
2021-07-19 22:50 ` Sean Christopherson
2021-07-20 14:37 ` Brijesh Singh
2021-07-20 16:28 ` Sean Christopherson
2021-07-20 18:21 ` Brijesh Singh
2021-07-20 22:09 ` Sean Christopherson
2021-07-07 18:36 ` [PATCH Part2 RFC v4 39/40] KVM: SVM: Use a VMSA physical address variable for populating VMCB Brijesh Singh
2021-07-21 0:20 ` Sean Christopherson
2021-07-21 16:26 ` Tom Lendacky
2021-07-07 18:36 ` [PATCH Part2 RFC v4 40/40] KVM: SVM: Support SEV-SNP AP Creation NAE event Brijesh Singh
2021-07-21 0:01 ` Sean Christopherson
2021-07-21 17:47 ` Tom Lendacky
2021-07-21 19:52 ` Sean Christopherson
2021-08-20 14:44 ` Tom Lendacky
2021-07-08 15:40 ` [PATCH Part2 RFC v4 00/40] Add AMD Secure Nested Paging (SEV-SNP) Hypervisor Support Dave Hansen
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=YPHhVZLyb795z/88@google.com \
--to=seanjc@google.com \
--cc=ardb@kernel.org \
--cc=bp@alien8.de \
--cc=brijesh.ksingh@gmail.com \
--cc=brijesh.singh@amd.com \
--cc=dave.hansen@linux.intel.com \
--cc=dovmurik@linux.ibm.com \
--cc=hpa@zytor.com \
--cc=jmattson@google.com \
--cc=jroedel@suse.de \
--cc=kvm@vger.kernel.org \
--cc=linux-coco@lists.linux.dev \
--cc=linux-crypto@vger.kernel.org \
--cc=linux-efi@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=luto@kernel.org \
--cc=michael.roth@amd.com \
--cc=mingo@redhat.com \
--cc=npmccallum@redhat.com \
--cc=pbonzini@redhat.com \
--cc=peterz@infradead.org \
--cc=pgonda@google.com \
--cc=platform-driver-x86@vger.kernel.org \
--cc=rientjes@google.com \
--cc=slp@redhat.com \
--cc=srinivas.pandruvada@linux.intel.com \
--cc=tglx@linutronix.de \
--cc=thomas.lendacky@amd.com \
--cc=tobin@ibm.com \
--cc=tony.luck@intel.com \
--cc=vbabka@suse.cz \
--cc=vkuznets@redhat.com \
--cc=wanpengli@tencent.com \
--cc=x86@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).