When a page triggers a machine check, it only reports the physical address of EPC page. But in order to inject #MC into hypervisor, the virtual address is required. Then repurpose the "owner" field as the virtual address of the virtual EPC page so that arch_memory_failure() can easily retrieve it. Add a new EPC page flag - SGX_EPC_PAGE_KVM_GUEST to interpret the meaning of the field. Co-developed-by: Cathy Zhang <cathy.zhang@xxxxxxxxx> Signed-off-by: Cathy Zhang <cathy.zhang@xxxxxxxxx> Signed-off-by: Zhiquan Li <zhiquan1.li@xxxxxxxxx> Acked-by: Kai Huang <kai.huang@xxxxxxxxx> --- Changes since V4: - Add Co-developed-by and Signed-off-by from Cathy Zhang, as she had fully discussed the flag name with Jarkko. Link: https://lore.kernel.org/all/df92395ade424401ac3c6322de568720@xxxxxxxxx/ - Add Acked-by from Kai Huang Link: https://lore.kernel.org/linux-sgx/0676cd4e-d94b-e904-81ae-ca1c05d37070@xxxxxxxxx/T/#mccfb11df30698dbd060f2b6f06383cda7f154ef3 Changes since V3: - Take the definition of EPC page flag SGX_EPC_PAGE_KVM_GUEST from Cathy Zhang's third patch of SGX rebootless recovery patch set but discard irrelevant portion, since it might need some time to re-forge and these are two different features. Link: https://lore.kernel.org/linux-sgx/41704e5d4c03b49fcda12e695595211d950cfb08.camel@xxxxxxxxxx/T/#m9782d23496cacecb7da07a67daa79f4b322ae170 Changes since V2: - Rework the patch suggested by Jarkko. - Remove struct sgx_vepc_page and relevant code. - Remove new EPC page flag SGX_EPC_PAGE_IS_VEPC definition as it is duplicated to SGX_EPC_PAGE_KVM_GUEST. Link: https://lore.kernel.org/linux-sgx/eb95b32ecf3d44a695610cf7f2816785@xxxxxxxxx/T/#u Changes since V1: - Add documentation suggested by Jarkko. --- arch/x86/kernel/cpu/sgx/sgx.h | 2 ++ arch/x86/kernel/cpu/sgx/virt.c | 4 +++- 2 files changed, 5 insertions(+), 1 deletion(-) diff --git a/arch/x86/kernel/cpu/sgx/sgx.h b/arch/x86/kernel/cpu/sgx/sgx.h index 0f17def9fe6f..b43582da1bcf 100644 --- a/arch/x86/kernel/cpu/sgx/sgx.h +++ b/arch/x86/kernel/cpu/sgx/sgx.h @@ -28,6 +28,8 @@ /* Pages on free list */ #define SGX_EPC_PAGE_IS_FREE BIT(1) +/* Pages allocated for KVM guest */ +#define SGX_EPC_PAGE_KVM_GUEST BIT(2) struct sgx_epc_page { unsigned int section; diff --git a/arch/x86/kernel/cpu/sgx/virt.c b/arch/x86/kernel/cpu/sgx/virt.c index 6a77a14eee38..776ae5c1c032 100644 --- a/arch/x86/kernel/cpu/sgx/virt.c +++ b/arch/x86/kernel/cpu/sgx/virt.c @@ -46,10 +46,12 @@ static int __sgx_vepc_fault(struct sgx_vepc *vepc, if (epc_page) return 0; - epc_page = sgx_alloc_epc_page(vepc, false); + epc_page = sgx_alloc_epc_page((void *)addr, false); if (IS_ERR(epc_page)) return PTR_ERR(epc_page); + epc_page->flags |= SGX_EPC_PAGE_KVM_GUEST; + ret = xa_err(xa_store(&vepc->page_array, index, epc_page, GFP_KERNEL)); if (ret) goto err_free; -- 2.25.1
