Searched hist:"1 d58a17e" (Results 1 – 3 of 3) sorted by relevance
/openbmc/linux/arch/arm64/kvm/hyp/include/nvhe/ |
H A D | gfp.h | 1d58a17e Tue Oct 05 04:01:41 CDT 2021 Quentin Perret <qperret@google.com> KVM: arm64: Fix host stage-2 PGD refcount
The KVM page-table library refcounts the pages of concatenated stage-2 PGDs individually. However, when running KVM in protected mode, the host's stage-2 PGD is currently managed by EL2 as a single high-order compound page, which can cause the refcount of the tail pages to reach 0 when they shouldn't, hence corrupting the page-table.
Fix this by introducing a new hyp_split_page() helper in the EL2 page allocator (matching the kernel's split_page() function), and make use of it from host_s2_zalloc_pages_exact().
Fixes: 1025c8c0c6ac ("KVM: arm64: Wrap the host with a stage 2") Acked-by: Will Deacon <will@kernel.org> Suggested-by: Will Deacon <will@kernel.org> Signed-off-by: Quentin Perret <qperret@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20211005090155.734578-5-qperret@google.com
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/openbmc/linux/arch/arm64/kvm/hyp/nvhe/ |
H A D | page_alloc.c | 1d58a17e Tue Oct 05 04:01:41 CDT 2021 Quentin Perret <qperret@google.com> KVM: arm64: Fix host stage-2 PGD refcount
The KVM page-table library refcounts the pages of concatenated stage-2 PGDs individually. However, when running KVM in protected mode, the host's stage-2 PGD is currently managed by EL2 as a single high-order compound page, which can cause the refcount of the tail pages to reach 0 when they shouldn't, hence corrupting the page-table.
Fix this by introducing a new hyp_split_page() helper in the EL2 page allocator (matching the kernel's split_page() function), and make use of it from host_s2_zalloc_pages_exact().
Fixes: 1025c8c0c6ac ("KVM: arm64: Wrap the host with a stage 2") Acked-by: Will Deacon <will@kernel.org> Suggested-by: Will Deacon <will@kernel.org> Signed-off-by: Quentin Perret <qperret@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20211005090155.734578-5-qperret@google.com
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H A D | mem_protect.c | 1d58a17e Tue Oct 05 04:01:41 CDT 2021 Quentin Perret <qperret@google.com> KVM: arm64: Fix host stage-2 PGD refcount
The KVM page-table library refcounts the pages of concatenated stage-2 PGDs individually. However, when running KVM in protected mode, the host's stage-2 PGD is currently managed by EL2 as a single high-order compound page, which can cause the refcount of the tail pages to reach 0 when they shouldn't, hence corrupting the page-table.
Fix this by introducing a new hyp_split_page() helper in the EL2 page allocator (matching the kernel's split_page() function), and make use of it from host_s2_zalloc_pages_exact().
Fixes: 1025c8c0c6ac ("KVM: arm64: Wrap the host with a stage 2") Acked-by: Will Deacon <will@kernel.org> Suggested-by: Will Deacon <will@kernel.org> Signed-off-by: Quentin Perret <qperret@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20211005090155.734578-5-qperret@google.com
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