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| author | Sean Christopherson <seanjc@google.com> | 2024-10-10 11:24:16 -0700 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2024-10-25 13:00:49 -0400 |
| commit | ee0fa693546decf6673a87e75dec39ed2ab1524b (patch) | |
| tree | 8f367136685d364b4fbdcd183aaf9474983251e0 /arch/powerpc/kvm | |
| parent | 17b7dbaf183e9cc131bbf5311db8202d323aa667 (diff) | |
| download | linux-ee0fa693546decf6673a87e75dec39ed2ab1524b.tar.gz linux-ee0fa693546decf6673a87e75dec39ed2ab1524b.tar.bz2 linux-ee0fa693546decf6673a87e75dec39ed2ab1524b.zip | |
KVM: PPC: Use kvm_vcpu_map() to map guest memory to patch dcbz instructions
Use kvm_vcpu_map() when patching dcbz in guest memory, as a regular GUP
isn't technically sufficient when writing to data in the target pages.
As per Documentation/core-api/pin_user_pages.rst:
Correct (uses FOLL_PIN calls):
pin_user_pages()
write to the data within the pages
unpin_user_pages()
INCORRECT (uses FOLL_GET calls):
get_user_pages()
write to the data within the pages
put_page()
As a happy bonus, using kvm_vcpu_{,un}map() takes care of creating a
mapping and marking the page dirty.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Tested-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <20241010182427.1434605-75-seanjc@google.com>
Diffstat (limited to 'arch/powerpc/kvm')
| -rw-r--r-- | arch/powerpc/kvm/book3s_pr.c | 13 |
1 files changed, 6 insertions, 7 deletions
diff --git a/arch/powerpc/kvm/book3s_pr.c b/arch/powerpc/kvm/book3s_pr.c index cd7ab6d85090..83bcdc80ce51 100644 --- a/arch/powerpc/kvm/book3s_pr.c +++ b/arch/powerpc/kvm/book3s_pr.c @@ -639,28 +639,27 @@ static void kvmppc_set_pvr_pr(struct kvm_vcpu *vcpu, u32 pvr) */ static void kvmppc_patch_dcbz(struct kvm_vcpu *vcpu, struct kvmppc_pte *pte) { - struct page *hpage; + struct kvm_host_map map; u64 hpage_offset; u32 *page; - int i; + int i, r; - hpage = gfn_to_page(vcpu->kvm, pte->raddr >> PAGE_SHIFT); - if (!hpage) + r = kvm_vcpu_map(vcpu, pte->raddr >> PAGE_SHIFT, &map); + if (r) return; hpage_offset = pte->raddr & ~PAGE_MASK; hpage_offset &= ~0xFFFULL; hpage_offset /= 4; - page = kmap_atomic(hpage); + page = map.hva; /* patch dcbz into reserved instruction, so we trap */ for (i=hpage_offset; i < hpage_offset + (HW_PAGE_SIZE / 4); i++) if ((be32_to_cpu(page[i]) & 0xff0007ff) == INS_DCBZ) page[i] &= cpu_to_be32(0xfffffff7); - kunmap_atomic(page); - put_page(hpage); + kvm_vcpu_unmap(vcpu, &map); } static bool kvmppc_visible_gpa(struct kvm_vcpu *vcpu, gpa_t gpa) |