From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marek =?utf-8?Q?Marczykowski-G=C3=B3recki?= Subject: Xen inside KVM on AMD: Linux HVM/PVH crashes on AP bring up Date: Mon, 16 Apr 2018 17:14:03 +0200 Message-ID: <20180416151403.GA2208@mail-itl> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============2250143717369728147==" Return-path: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" To: xen-devel , kvm@vger.kernel.org, Joerg Roedel List-Id: xen-devel@lists.xenproject.org --===============2250143717369728147== Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="FL5UXtIhxfXey3p5" Content-Disposition: inline --FL5UXtIhxfXey3p5 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hi, I' trying to boot Linux PVH on Xen, which is running inside KVM on AMD hardware. As soon as secondary CPU is starting, domain crashes. Strangely, without printing any related messages on the console. The last message is "x86: Booting SMP configuration:". This happens for both PVH and HVM with 2 vcpus. PVH/HVM domains with 1 vcpu works fine(*), as well as PV domains with multiple vcpus. Using gdbsx I've managed to get the point where it crashes: (gdb) f 12 #12 0xffffffff81025101 in do_error_trap (regs=3D0xffffc9000037fe78, err= or_code=3D-2401053088876204019,=20 str=3D0x40 , trapnr=3D6, signr=3D-2) at arch/x86/kernel/traps.c:302 302 arch/x86/kernel/traps.c: No such file or directory. (gdb) p/x *regs $8 =3D {r15 =3D 0x0, r14 =3D 0x0, r13 =3D 0x0, r12 =3D 0x0, bp =3D 0x1,= bx =3D 0xffff88007fd0f040, r11 =3D 0x0,=20 r10 =3D 0x0, r9 =3D 0x38, r8 =3D 0x0, ax =3D 0xffffffe4, cx =3D 0xfff= fffff82251e68, dx =3D 0x0, si =3D 0x96,=20 di =3D 0x82, orig_ax =3D 0xffffffffffffffff, ip =3D 0xffffffff81036bd= 3, cs =3D 0x10, flags =3D 0x10086,=20 sp =3D 0xffffc9000037ff20, ss =3D 0x0} (gdb) info symbol 0xffffffff81036bd3 identify_secondary_cpu + 83 in section .text It is BUG_ON(c =3D=3D &boot_cpu_data). If I read it correctly, "c" is 0x82, which indeed isn't &boot_cpu_data (0xffffffff8234fe00). Any idea? Version info: Linux (L0, KVM): 4.4.114-42 (OpenSUSE Leap 42.3) Xen (L1): 4.8.3 Linux dom0 (L1): 4.14.18 Linux guest: 4.14.18 (*) besides some 20s+ delay on flush_work in deferred_probe_initcall, before actually calling deferred_probe_work_func. --=20 Best Regards, Marek Marczykowski-G=C3=B3recki Invisible Things Lab A: Because it messes up the order in which people normally read text. Q: Why is top-posting such a bad thing? --FL5UXtIhxfXey3p5 Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEEhrpukzGPukRmQqkK24/THMrX1ywFAlrRz/kACgkQ24/THMrX 1yzsQAf/Wf/zIy0iR9RfdvOy3W5nU6gkUQZwLVgddvpDE2g4r8+MGMwy8U6Gpc4X tk9fjB/IMFuLbyBGmAvZ4n6+/aUEH2RVRKH72tMeyeL9X0ot9FgGkxDxVDcgaIwa tH5oWX2j5hZnzbXKuOvLnvZ0E0cwSCs4kplkX9cvC6O8NDkm8VZvRciHy4lohgNN VsVvqFkLl1DUhN9lVuPBBkJOcdNyEIw8A4qiyghmH6XjDizZvXAJLkuEuNgBpErT 7ye1lDsjmQvdU3jnc28Q+xypbaArYaBt4e+3TaMEYL5iUHaBgd3OKkXvsVhYEvY3 PtxvhpqbMYlr8j8/zQxDUu/LBJVxdA== =47wD -----END PGP SIGNATURE----- --FL5UXtIhxfXey3p5-- --===============2250143717369728147== Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: base64 Content-Disposition: inline X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX18KWGVuLWRldmVs IG1haWxpbmcgbGlzdApYZW4tZGV2ZWxAbGlzdHMueGVucHJvamVjdC5vcmcKaHR0cHM6Ly9saXN0 cy54ZW5wcm9qZWN0Lm9yZy9tYWlsbWFuL2xpc3RpbmZvL3hlbi1kZXZlbA== --===============2250143717369728147==--