Re: [PATCH Part1 RFC v4 20/36] x86/sev: Use SEV-SNP AP creation to start secondary CPUs
From: Borislav Petkov <bp@alien8.de>
Date: 2021-08-17 20:03:56
Also in:
kvm, linux-coco, linux-efi, linux-mm, lkml, platform-driver-x86
On Wed, Jul 07, 2021 at 01:14:50PM -0500, Brijesh Singh wrote:
quoted hunk ↗ jump to hunk
@@ -854,6 +858,207 @@ void snp_set_memory_private(unsigned long vaddr, unsigned int npages) pvalidate_pages(vaddr, npages, 1); } +static int vmsa_rmpadjust(void *va, bool vmsa)
I know, I know it gets a bool vmsa param but you can still call it simply rmpadjust() because this is what it does - it is a wrapper around the insn. Just like pvalidate() and so on. ...
+static int wakeup_cpu_via_vmgexit(int apic_id, unsigned long start_ip)
+{
+ struct sev_es_save_area *cur_vmsa, *vmsa;
+ struct ghcb_state state;
+ unsigned long flags;
+ struct ghcb *ghcb;
+ int cpu, err, ret;
+ u8 sipi_vector;
+ u64 cr4;
+
+ if ((sev_hv_features & GHCB_HV_FT_SNP_AP_CREATION) != GHCB_HV_FT_SNP_AP_CREATION)
+ return -EOPNOTSUPP;
+
+ /*
+ * Verify the desired start IP against the known trampoline start IP
+ * to catch any future new trampolines that may be introduced that
+ * would require a new protected guest entry point.
+ */
+ if (WARN_ONCE(start_ip != real_mode_header->trampoline_start,
+ "unsupported SEV-SNP start_ip: %lx\n", start_ip))"Unsupported... " - with a capital letter
+ return -EINVAL; + + /* Override start_ip with known protected guest start IP */ + start_ip = real_mode_header->sev_es_trampoline_start; +
...
--
Regards/Gruss,
Boris.
https://people.kernel.org/tglx/notes-about-netiquette