i386: Fix legacy guest with xsave panic on host kvm without update cpuid.
without kvm commit
412a3c41, CPUID(EAX=0xd,ECX=0).EBX always equal to 0 even
through guest update xcr0, this will crash legacy guest(e.g., CentOS 6).
Below is the call trace on the guest.
[ 0.000000] kernel BUG at mm/bootmem.c:469!
[ 0.000000] invalid opcode: 0000 [#1] SMP
[ 0.000000] last sysfs file:
[ 0.000000] CPU 0
[ 0.000000] Modules linked in:
[ 0.000000]
[ 0.000000] Pid: 0, comm: swapper Tainted: G --------------- H 2.6.32-279#2 Red Hat KVM
[ 0.000000] RIP: 0010:[<
ffffffff81c4edc4>] [<
ffffffff81c4edc4>] alloc_bootmem_core+0x7b/0x29e
[ 0.000000] RSP: 0018:
ffffffff81a01cd8 EFLAGS:
00010046
[ 0.000000] RAX:
ffffffff81cb1748 RBX:
ffffffff81cb1720 RCX:
0000000001000000
[ 0.000000] RDX:
0000000000000040 RSI:
0000000000000000 RDI:
ffffffff81cb1720
[ 0.000000] RBP:
ffffffff81a01d38 R08:
0000000000000000 R09:
0000000000001000
[ 0.000000] R10:
02008921da802087 R11:
00000000ffff8800 R12:
0000000000000000
[ 0.000000] R13:
0000000000000000 R14:
0000000000000000 R15:
0000000001000000
[ 0.000000] FS:
0000000000000000(0000) GS:
ffff880002200000(0000) knlGS:
0000000000000000
[ 0.000000] CS: 0010 DS: 0018 ES: 0018 CR0:
0000000080050033
[ 0.000000] CR2:
0000000000000000 CR3:
0000000001a85000 CR4:
00000000001406b0
[ 0.000000] DR0:
0000000000000000 DR1:
0000000000000000 DR2:
0000000000000000
[ 0.000000] DR3:
0000000000000000 DR6:
00000000ffff0ff0 DR7:
0000000000000400
[ 0.000000] Process swapper (pid: 0, threadinfo
ffffffff81a00000, task
ffffffff81a8d020)
[ 0.000000] Stack:
[ 0.000000]
0000000000000002 81a01dd881eaf060 000000007e5fe227 0000000000001001
[ 0.000000] <d>
0000000000000040 0000000000000001 0000006cffffffff 0000000001000000
[ 0.000000] <d>
ffffffff81cb1720 0000000000000000 0000000000000000 0000000000000000
[ 0.000000] Call Trace:
[ 0.000000] [<
ffffffff81c4f074>] ___alloc_bootmem_nopanic+0x8d/0xca
[ 0.000000] [<
ffffffff81c4f0cf>] ___alloc_bootmem+0x11/0x39
[ 0.000000] [<
ffffffff81c4f172>] __alloc_bootmem+0xb/0xd
[ 0.000000] [<
ffffffff814d42d9>] xsave_cntxt_init+0x249/0x2c0
[ 0.000000] [<
ffffffff814e0689>] init_thread_xstate+0x17/0x25
[ 0.000000] [<
ffffffff814e0710>] fpu_init+0x79/0xaa
[ 0.000000] [<
ffffffff814e27e3>] cpu_init+0x301/0x344
[ 0.000000] [<
ffffffff81276395>] ? sort+0x155/0x230
[ 0.000000] [<
ffffffff81c30cf2>] trap_init+0x24e/0x25f
[ 0.000000] [<
ffffffff81c2bd73>] start_kernel+0x21c/0x430
[ 0.000000] [<
ffffffff81c2b33a>] x86_64_start_reservations+0x125/0x129
[ 0.000000] [<
ffffffff81c2b438>] x86_64_start_kernel+0xfa/0x109
[ 0.000000] Code: 03 48 89 f1 49 c1 e8 0c 48 0f af d0 48 c7 c6 00 a6 61 81 48 c7 c7 00 e5 79 81 31 c0 4c 89 74 24 08 e8 f2 d7 89 ff 4d 85 e4 75 04 <0f> 0b eb fe 48 8b 45 c0 48 83 e8 01 48 85 45
c0 74 04 0f 0b eb
Signed-off-by: Bingsong Si <owen.si@ucloud.cn>
Message-Id: <
20190822042901.16858-1-owen.si@ucloud.cn>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>