Date: Tue, 9 Jan 2018 14:22:19 +0000 (UTC) From: Andriy Gapon <avg@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r327726 - head/sys/amd64/vmm/amd Message-ID: <201801091422.w09EMJpB029552@repo.freebsd.org>
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Author: avg Date: Tue Jan 9 14:22:18 2018 New Revision: 327726 URL: https://svnweb.freebsd.org/changeset/base/327726 Log: vmm/svm: contigmalloc of the whole svm_softc is excessive This is a followup to r307903. struct svm_softc takes more than 200 kilobytes while what we really need is 3 contiguous pages for I/O permission map and 2 contiguous pages for MSR permission map. Other physically mapped structures have a size of a single page, so a proper alignment is sufficient for their correct mapping. Thus, only the permission maps are allocated with contigmalloc now, the softc is allocated with a regular malloc. Additionally, this commit adds a check that malloc returns memory with the expected page alignment and that contigmalloc does not fail. Unfortunately, at present svm_vminit() is expected to always succeed and there is no way to report an error. So, a contigmalloc failure leads to a panic. We should probably fix this. MFC after: 2 weeks Modified: head/sys/amd64/vmm/amd/svm.c head/sys/amd64/vmm/amd/svm_softc.h Modified: head/sys/amd64/vmm/amd/svm.c ============================================================================== --- head/sys/amd64/vmm/amd/svm.c Tue Jan 9 13:43:04 2018 (r327725) +++ head/sys/amd64/vmm/amd/svm.c Tue Jan 9 14:22:18 2018 (r327726) @@ -517,15 +517,26 @@ svm_vminit(struct vm *vm, pmap_t pmap) vm_paddr_t msrpm_pa, iopm_pa, pml4_pa; int i; - svm_sc = contigmalloc(sizeof (*svm_sc), M_SVM, M_WAITOK | M_ZERO, - 0, ~(vm_paddr_t)0, PAGE_SIZE, 0); + svm_sc = malloc(sizeof (*svm_sc), M_SVM, M_WAITOK | M_ZERO); + if (((uintptr_t)svm_sc & PAGE_MASK) != 0) + panic("malloc of svm_softc not aligned on page boundary"); + + svm_sc->msr_bitmap = contigmalloc(SVM_MSR_BITMAP_SIZE, M_SVM, + M_WAITOK, 0, ~(vm_paddr_t)0, PAGE_SIZE, 0); + if (svm_sc->msr_bitmap == NULL) + panic("contigmalloc of SVM MSR bitmap failed"); + svm_sc->iopm_bitmap = contigmalloc(SVM_IO_BITMAP_SIZE, M_SVM, + M_WAITOK, 0, ~(vm_paddr_t)0, PAGE_SIZE, 0); + if (svm_sc->iopm_bitmap == NULL) + panic("contigmalloc of SVM IO bitmap failed"); + svm_sc->vm = vm; svm_sc->nptp = (vm_offset_t)vtophys(pmap->pm_pml4); /* * Intercept read and write accesses to all MSRs. */ - memset(svm_sc->msr_bitmap, 0xFF, sizeof(svm_sc->msr_bitmap)); + memset(svm_sc->msr_bitmap, 0xFF, SVM_MSR_BITMAP_SIZE); /* * Access to the following MSRs is redirected to the VMCB when the @@ -553,7 +564,7 @@ svm_vminit(struct vm *vm, pmap_t pmap) svm_msr_rd_ok(svm_sc->msr_bitmap, MSR_EFER); /* Intercept access to all I/O ports. */ - memset(svm_sc->iopm_bitmap, 0xFF, sizeof(svm_sc->iopm_bitmap)); + memset(svm_sc->iopm_bitmap, 0xFF, SVM_IO_BITMAP_SIZE); iopm_pa = vtophys(svm_sc->iopm_bitmap); msrpm_pa = vtophys(svm_sc->msr_bitmap); @@ -2043,7 +2054,9 @@ svm_vmcleanup(void *arg) { struct svm_softc *sc = arg; - contigfree(sc, sizeof (*sc), M_SVM); + contigfree(sc->iopm_bitmap, SVM_IO_BITMAP_SIZE, M_SVM); + contigfree(sc->msr_bitmap, SVM_MSR_BITMAP_SIZE, M_SVM); + free(sc, M_SVM); } static register_t * Modified: head/sys/amd64/vmm/amd/svm_softc.h ============================================================================== --- head/sys/amd64/vmm/amd/svm_softc.h Tue Jan 9 13:43:04 2018 (r327725) +++ head/sys/amd64/vmm/amd/svm_softc.h Tue Jan 9 14:22:18 2018 (r327726) @@ -56,13 +56,13 @@ struct svm_vcpu { * SVM softc, one per virtual machine. */ struct svm_softc { - uint8_t iopm_bitmap[SVM_IO_BITMAP_SIZE]; /* shared by all vcpus */ - uint8_t msr_bitmap[SVM_MSR_BITMAP_SIZE]; /* shared by all vcpus */ uint8_t apic_page[VM_MAXCPU][PAGE_SIZE]; struct svm_vcpu vcpu[VM_MAXCPU]; vm_offset_t nptp; /* nested page table */ + uint8_t *iopm_bitmap; /* shared by all vcpus */ + uint8_t *msr_bitmap; /* shared by all vcpus */ struct vm *vm; -} __aligned(PAGE_SIZE); +}; CTASSERT((offsetof(struct svm_softc, nptp) & PAGE_MASK) == 0);
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