On Thu, Aug 29, 2024 at 04:36:21PM +0200, David Hildenbrand wrote: > On 29.08.24 13:28, Aithal, Srikanth wrote: > > Hello, > > > > Starting linux-next20240827 build, running QEMU KVM instance with option > > to freeze the CPU at the very beginning and then continue results in > > below guest crash. Disabling CONFIG_KSM will make this issue go away. > > Same issue exists with todays linux-next as well. > > > > /SecCoreStartupWithStack(0xFFFCC000, 0x820000) > > error: kvm run failed Bad address > > RAX=0000000000232000 RBX=00000000fffdb101 RCX=000000000081fab0 > > RDX=00000000fffd7b03 > > RSI=0000000000807000 RDI=00000000fffd262b RBP=000000000081fc00 > > RSP=000000000081faa0 > > R8 =00000000fffd7af7 R9 =0000000000000071 R10=0000000000400000 > > R11=0000000000000000 > > R12=00000000fffcc094 R13=00000000fffcc000 R14=00000000ffdce000 > > R15=0000000000000600 > > RIP=00000000fffd1cb5 RFL=00000087 [--S--PC] CPL=0 II=0 A20=1 SMM=0 HLT=0 > > ES =0018 0000000000000000 ffffffff 00c09300 DPL=0 DS [-WA] > > CS =0038 0000000000000000 ffffffff 00a09b00 DPL=0 CS64 [-RA] > > SS =0018 0000000000000000 ffffffff 00c09300 DPL=0 DS [-WA] > > DS =0018 0000000000000000 ffffffff 00c09300 DPL=0 DS [-WA] > > FS =0018 0000000000000000 ffffffff 00c09300 DPL=0 DS [-WA] > > GS =0018 0000000000000000 ffffffff 00c09300 DPL=0 DS [-WA] > > LDT=0000 0000000000000000 0000ffff 00008200 DPL=0 LDT > > TR =0000 0000000000000000 0000ffff 00008b00 DPL=0 TSS64-busy > > GDT= 00000000fffffed0 0000003f > > IDT= 000000000081fd70 0000021f > > CR0=80000033 CR2=0000000000000000 CR3=0000000000800000 CR4=00000660 > > DR0=0000000000000000 DR1=0000000000000000 DR2=0000000000000000 > > DR3=0000000000000000 > > DR6=00000000ffff0ff0 DR7=0000000000000400 > > EFER=0000000000000500 > > Code=05 00 10 00 00 49 81 ee 00 10 00 00 48 3d 00 00 00 02 77 12 <41> 81 > > 7e 28 5f 46 56 48 75 e1 49 3b 46 20 73 05 eb d9 4d 89 ee 48 8d 8d 10 ff > > ff ff ba 02 > > / > > > > _Host dmesg throws:_ > > > > /[ 232.158038] BUG: Bad page state in process ksmd pfn:404740a > > [ 232.164393] page: refcount:0 mapcount:1 mapping:0000000000000000 > > index:0x7f8687c0a pfn:0x404740a > > [ 232.164401] flags: 0x17ffffc0020819(locked|uptodate|dirty|owner_2|swapbacked|node=0|zone=2|lastcpupid=0x1fffff) > > [ 232.164412] raw: 0017ffffc0020819 dead000000000100 dead000000000122 > > 0000000000000000 > > [ 232.164417] raw: 00000007f8687c0a 0000000000000000 0000000000000000 > > 0000000000000000 > > [ 232.164420] page dumped because: PAGE_FLAGS_CHECK_AT_FREE flag(s) set > > Might be related to Willy's page flag rework. Not 100% sure, though, what's > happening here. > > Is there a way to revert the recent changes from Willy to > include/linux/page-flags.h and see if the problem goes away? Looks like the same signature as https://lore.kernel.org/linux-mm/yt9dttf3r49e.fsf@xxxxxxxxxxxxx/