https://bugzilla.kernel.org/show_bug.cgi?id=217796 Bug ID: 217796 Summary: latest Zen Inception fixes breaks nested kvm virtualization on AMD Product: Virtualization Version: unspecified Hardware: AMD OS: Linux Status: NEW Severity: blocking Priority: P3 Component: kvm Assignee: virtualization_kvm@xxxxxxxxxxxxxxxxxxxx Reporter: sonst+kernel@xxxxxxxxxxx Regression: No Hi all, today I updated to 6.4.10 on arch linux. This broke my setup with running a KVM nested virtualization within a KVM VM. Problem seems kernel update related not distribution specific since others report same issue on a totally different setup: https://forum.proxmox.com/threads/amd-incpetion-fixes-cause-qemu-kvm-memory-leak.132057/#post-581207 Issue: 1. Start KVM vm ("hostVM") with 60GB memory assigned -> all works. 2. within that hostVM I start a nestedVM with 5GB memory assigned. 3. Memory consumption of the quemu process within the hostVM goes beyond available memory. Then the nestedVM gets OOM killed before even being started using more than the 60GB + Swap. I tried to setup fresh nestedVMs with no luck, same problem. Reverting to an earlier kernel (6.4.7 on arch linux) lets everything work again. host kernel: 6.4.10-arch1 (this induces the problems, rest was unchanged) hostVM kernel: 5.15.107+truenas nestedVM kernel: 5.15.0-78-generic Logs from the hostVM when OOM happens: Aug 15 10:59:41 truenas kernel: CPU 0/KVM invoked oom-killer: gfp_mask=0x400dc0(GFP_KERNEL_ACCOUNT|__GFP_ZERO), order=0, oom_score_adj=0 Aug 15 10:59:42 truenas kernel: CPU: 9 PID: 7079 Comm: CPU 0/KVM Tainted: P OE 5.15.107+truenas #1 Aug 15 10:59:43 truenas kernel: Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS unknown 2/2/2022 Aug 15 10:59:43 truenas kernel: Call Trace: Aug 15 10:59:43 truenas kernel: <TASK> Aug 15 10:59:43 truenas kernel: dump_stack_lvl+0x46/0x5e Aug 15 10:59:43 truenas kernel: dump_header+0x4a/0x1f4 Aug 15 10:59:43 truenas kernel: oom_kill_process.cold+0xb/0x10 Aug 15 10:59:43 truenas kernel: out_of_memory+0x1bd/0x4f0 Aug 15 10:59:43 truenas kernel: __alloc_pages_slowpath.constprop.0+0xc30/0xd00 Aug 15 10:59:44 truenas kernel: __alloc_pages+0x1e9/0x220 Aug 15 10:59:44 truenas kernel: __get_free_pages+0xd/0x40 Aug 15 10:59:44 truenas kernel: kvm_mmu_topup_memory_cache+0x56/0x80 [kvm] Aug 15 10:59:44 truenas kernel: mmu_topup_memory_caches+0x39/0x70 [kvm] Aug 15 10:59:44 truenas kernel: direct_page_fault+0x3d9/0xbb0 [kvm] Aug 15 10:59:44 truenas kernel: ? kvm_mtrr_check_gfn_range_consistency+0x61/0x120 [kvm] Aug 15 10:59:44 truenas kernel: kvm_mmu_page_fault+0x7a/0x730 [kvm] Aug 15 10:59:44 truenas kernel: ? ktime_get+0x38/0xa0 Aug 15 10:59:44 truenas kernel: ? lock_timer_base+0x61/0x80 Aug 15 10:59:44 truenas kernel: ? __svm_vcpu_run+0x5f/0xf0 [kvm_amd] Aug 15 10:59:44 truenas kernel: ? __svm_vcpu_run+0x59/0xf0 [kvm_amd] Aug 15 10:59:44 truenas kernel: ? __svm_vcpu_run+0xaa/0xf0 [kvm_amd] Aug 15 10:59:44 truenas kernel: ? load_fixmap_gdt+0x22/0x30 Aug 15 10:59:44 truenas kernel: ? native_load_tr_desc+0x67/0x70 Aug 15 10:59:44 truenas kernel: ? x86_virt_spec_ctrl+0x43/0xb0 Aug 15 10:59:44 truenas kernel: kvm_arch_vcpu_ioctl_run+0xbff/0x1750 [kvm] Aug 15 10:59:44 truenas kernel: kvm_vcpu_ioctl+0x278/0x660 [kvm] Aug 15 10:59:44 truenas kernel: ? __seccomp_filter+0x385/0x5c0 Aug 15 10:59:44 truenas kernel: __x64_sys_ioctl+0x8b/0xc0 Aug 15 10:59:44 truenas kernel: do_syscall_64+0x3b/0xc0 Aug 15 10:59:44 truenas kernel: entry_SYSCALL_64_after_hwframe+0x61/0xcb Aug 15 10:59:44 truenas kernel: RIP: 0033:0x7f29eee166b7 Aug 15 10:59:45 truenas kernel: Code: Unable to access opcode bytes at RIP 0x7f29eee1668d. Aug 15 10:59:45 truenas kernel: RSP: 002b:00007f27f35fd4c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 Aug 15 10:59:45 truenas kernel: RAX: ffffffffffffffda RBX: 000000000000ae80 RCX: 00007f29eee166b7 Aug 15 10:59:45 truenas kernel: RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000015 Aug 15 10:59:45 truenas kernel: RBP: 00005558a87d3f00 R08: 00005558a7e52848 R09: 00005558a827c580 Aug 15 10:59:45 truenas kernel: R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 Aug 15 10:59:45 truenas kernel: R13: 00005558a8298bc0 R14: 00007f27f35fd780 R15: 0000000000802000 Aug 15 10:59:45 truenas kernel: </TASK> Aug 15 10:59:45 truenas kernel: Mem-Info: -- You may reply to this email to add a comment. You are receiving this mail because: You are watching the assignee of the bug.
