From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jay Lan Date: Wed, 14 Mar 2007 15:55:51 +0000 Subject: Re: [Patch] min_low_pfn and max_low_pfn calcultion fix Message-Id: <45F81B07.6020509@sgi.com> List-Id: References: <1172619535.20006.334.camel@linux-znh> In-Reply-To: <1172619535.20006.334.camel@linux-znh> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable To: linux-ia64@vger.kernel.org Jay Lan wrote: > Magnus Damm wrote: > [snip] >>> I tested on 2.6.21-rc3 with DEBUG_VM turned on. The vanilla 2.6.21-rc3 >>> without Nan-hai's patch, panicked on bugcheck on free_initmem->free_page >>> as predicted. We still need this patch. >> Ok, thanks for testing. =3D) >> >>> However, the zero-size vmcore problem is back on SN. But that is a >>> dfiffernet problem. >> Argh, more problems... >=20 > I found the problem. It was the "elfcorehdr" introduced in 2.6.21-rc1. > Without specifying it, the elfcorehdr_addr is initialized to > ELFCORE_ADDR_MAX. Later, a check in reserve_elfcorehdr will fail: > if (elfcorehdr_addr >=3D ELFCORE_ADDR_MAX) > return -EINVAL; >=20 > Is it supposed to be a physical address to store elf core header? > If so, it is not possible for SN to provide a physical address at > boot time, just like in the case of crashkernel=3DX@Y where Y is not used. Sorry, the elfcorehdr parameter is provided to the kdump kernel by kexec. The problem is in the reserve_elfcorehdr logic introduced in 2.6.21-rc1. When booting up the kdump kernel, i observed a failure in reserve_elfcorehdr. The below are my debugging messages: elfcorehdr_addr027fe4000, ELFCORE_ADDR_MAX=FFffffffffffffff Cannot locate EFI vmcore descriptor reserve_elfcorehdr: vmcore descriptor size =3D 0 reserve_memory: FAIL to reserve reserve_elfcorehdr - jay >=20 > Thanks, > - jay >=20 >=20 >> / magnus >> - >> To unsubscribe from this list: send the line "unsubscribe linux-ia64" in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html >=20