From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:55382) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1f8JxR-0002w1-M7 for qemu-devel@nongnu.org; Tue, 17 Apr 2018 02:19:14 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1f8JxQ-0006iG-Bp for qemu-devel@nongnu.org; Tue, 17 Apr 2018 02:19:13 -0400 Date: Tue, 17 Apr 2018 16:19:00 +1000 From: David Gibson Message-ID: <20180417061900.GB2317@umbus.fritz.box> References: <1523472120-56496-1-git-send-email-spopovyc@redhat.com> <1523472120-56496-2-git-send-email-spopovyc@redhat.com> <20180413075739.GC14855@in.ibm.com> <20180417035842.GA3942@in.ibm.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="24zk1gE8NUlDmwG9" Content-Disposition: inline In-Reply-To: <20180417035842.GA3942@in.ibm.com> Subject: Re: [Qemu-devel] [PATCH for 2.13 v3 1/2] spapr: Add ibm, max-associativity-domains property List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Bharata B Rao Cc: Serhii Popovych , qemu-ppc@nongnu.org, qemu-devel@nongnu.org --24zk1gE8NUlDmwG9 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue, Apr 17, 2018 at 09:28:42AM +0530, Bharata B Rao wrote: > On Mon, Apr 16, 2018 at 07:47:29PM +0300, Serhii Popovych wrote: > > Bharata B Rao wrote: > > > On Wed, Apr 11, 2018 at 02:41:59PM -0400, Serhii Popovych wrote: > > >> Now recent kernels (i.e. since linux-stable commit a346137e9142 > > >> ("powerpc/numa: Use ibm,max-associativity-domains to discover possib= le nodes") > > >> support this property to mark initially memory-less NUMA nodes as "p= ossible" > > >> to allow further memory hot-add to them. > > >> > > >> Advertise this property for pSeries machines to let guest kernels de= tect > > >> maximum supported node configuration and benefit from kernel side ch= ange > > >> when hot-add memory to specific, possibly empty before, NUMA node. > > >> > > >> Signed-off-by: Serhii Popovych > > >> --- > > >> hw/ppc/spapr.c | 10 ++++++++++ > > >> 1 file changed, 10 insertions(+) > > >> > > >> diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c > > >> index a81570e..c05bbad 100644 > > >> --- a/hw/ppc/spapr.c > > >> +++ b/hw/ppc/spapr.c > > >> @@ -910,6 +910,13 @@ static void spapr_dt_rtas(sPAPRMachineState *sp= apr, void *fdt) > > >> 0, cpu_to_be32(SPAPR_MEMORY_BLOCK_SIZE), > > >> cpu_to_be32(max_cpus / smp_threads), > > >> }; > > >> + uint32_t maxdomains[] =3D { > > >> + cpu_to_be32(4), > > >> + cpu_to_be32(0), > > >> + cpu_to_be32(0), > > >> + cpu_to_be32(0), > > >> + cpu_to_be32(nb_numa_nodes - 1), > > >> + }; > > >> > > >> _FDT(rtas =3D fdt_add_subnode(fdt, 0, "rtas")); > > >> > > >> @@ -946,6 +953,9 @@ static void spapr_dt_rtas(sPAPRMachineState *spa= pr, void *fdt) > > >> _FDT(fdt_setprop(fdt, rtas, "ibm,associativity-reference-points= ", > > >> refpoints, sizeof(refpoints))); > > >> > > >> + _FDT(fdt_setprop(fdt, rtas, "ibm,max-associativity-domains", > > >> + maxdomains, sizeof(maxdomains))); > > >> + > > >> _FDT(fdt_setprop_cell(fdt, rtas, "rtas-error-log-max", > > >> RTAS_ERROR_LOG_MAX)); > > >> _FDT(fdt_setprop_cell(fdt, rtas, "rtas-event-scan-rate", > > >=20 > > > This commit causes hash guest with latest guest kernel to hang at ear= ly boot. > >=20 > > I use v4.16 tag from stable and can't reproduce on P8 machine reported > > issue. > >=20 > > Could you please share more details about your setup, kernel commit id > > you spot problem? >=20 > I am on 4.16.0-rc7 (commit id: 0b412605ef5f) >=20 > BTW this happens only for non-NUMA guest. Ah, that might explain it. With no NUMA nodes specified, I think this code will put a -1 into the max-associativity-domains property, which is probably causing the mess. If we don't have NUMA (nb_numa_nodes =3D=3D 0) we probably want to either omit the property entirely, or clamp that 5th cell to 0. --=20 David Gibson | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ | _way_ _around_! http://www.ozlabs.org/~dgibson --24zk1gE8NUlDmwG9 Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAEBCAAdFiEEdfRlhq5hpmzETofcbDjKyiDZs5IFAlrVkdIACgkQbDjKyiDZ s5LnEA/+I1b8iB49+lCoHNVImwqDkxE3XzKDYIHFtTWVpR07JNKb7ylTy6qhqUOp dKONBJ/1MP3VUSbh4hrOznPtx4fbyhuPym7rCUEY4pQvh/hKboDPAxmdLcbJ74ct VOqFWSCQwANuWrZ7CbvtSbFPZiAT6+YnJTatNZYo0xSWVO2ukQ3W05k+azOYrTLY E/3LY/OvGJy8cj05OGuN+AaoZLw1S9LhU/XNtDON2EHJeLLhCifU4BtI8+C+bo28 Z/njAGM7GQ/9NVU/QCif+4ebdzeqkmumqefvfAQDJgQtSq2wfMIH2RMnmnHaQYxR 8ERQ3E+6AV+3qAdD09vrCRGAUlCh/wsqr5D7iHvdKGozJGl97U+rFCL0HmYGGRCC DrXWdy/RzLH99FYa0jE7xYRDZeAc0SZO8cymYhagaGvqVuj+0REP93ateDRtlR+R d9HpEPk+bg8lykdy0NZTDo60X2uNhdfwprlL43qlCWKZ1rzqLAZM3SgYwEkHE6IP Sc7ZXsDImfoFUh+g+ZdgSeckWJRk/wEnZVzZnoMB3URiMjJSej+yXhit9M/QJCs5 8wXKCyLKVygyZY+JNOUZ9XWpbt0VpyKhHtnlX5SmSqUR6ngeriW5Qjk/ft93U8uL iQtjBeBmTfVh9i4z8TmyLm/SPWWFB+ydP9u979sQIQX2WyxSq1U= =w75Z -----END PGP SIGNATURE----- --24zk1gE8NUlDmwG9--