On Tue, Jan 24, 2023, Liam Merwick wrote: > On 14/01/2023 00:37, Sean Christopherson wrote: > > On Fri, Dec 02, 2022, Chao Peng wrote: > > > This patch series implements KVM guest private memory for confidential > > > computing scenarios like Intel TDX[1]. If a TDX host accesses > > > TDX-protected guest memory, machine check can happen which can further > > > crash the running host system, this is terrible for multi-tenant > > > configurations. The host accesses include those from KVM userspace like > > > QEMU. This series addresses KVM userspace induced crash by introducing > > > new mm and KVM interfaces so KVM userspace can still manage guest memory > > > via a fd-based approach, but it can never access the guest memory > > > content. > > > > > > The patch series touches both core mm and KVM code. I appreciate > > > Andrew/Hugh and Paolo/Sean can review and pick these patches. Any other > > > reviews are always welcome. > > > - 01: mm change, target for mm tree > > > - 02-09: KVM change, target for KVM tree > > > > A version with all of my feedback, plus reworked versions of Vishal's selftest, > > is available here: > > > > git@xxxxxxxxxx:sean-jc/linux.git x86/upm_base_support > > > > It compiles and passes the selftest, but it's otherwise barely tested. There are > > a few todos (2 I think?) and many of the commits need changelogs, i.e. it's still > > a WIP. > > > > When running LTP (https://github.com/linux-test-project/ltp) on the v10 > bits (and also with Sean's branch above) I encounter the following NULL > pointer dereference with testcases/kernel/syscalls/madvise/madvise01 > (100% reproducible). > > It appears that in restrictedmem_error_page() inode->i_mapping->private_data > is NULL > in the list_for_each_entry_safe(inode, next, &sb->s_inodes, i_sb_list) > but I don't know why. Kirill, can you take a look? Or pass the buck to someone who can? :-)
