From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mukesh Rathor Subject: Re: 32bit PAE PV guest on 64bit hypervisor Date: Tue, 14 Apr 2009 11:06:18 -0700 Message-ID: <49E4D09A.2020702@oracle.com> References: <49E40563.4010505@oracle.com> <49E4B2F3.1050307@goop.org> Reply-To: mukesh.rathor@oracle.com Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <49E4B2F3.1050307@goop.org> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Jeremy Fitzhardinge Cc: xen-devel List-Id: xen-devel@lists.xenproject.org Jeremy Fitzhardinge wrote: > Mukesh Rathor wrote: >> Hi, >> >> Been chasing down this message from guest boot: >> >> (XEN) mm.c:1841:d1 Error pfn 7f36a: rd=ffff8300cea28080, >> od=0000000000000000, caf=00000000, taf=0000000000000000 >> (XEN) mm.c:730:d1 Error getting mfn 7f36a (pfn 5555555555555555) from L1 >> entry 000000007f36a025 for dom1 >> (XEN) mm.c:3700:d1 ptwr_emulate: fixing up invalid PAE PTE >> 000000007f36a025 >> >> Firstly, on a >64GB system, looks like a 32bit guest can get mfn above >> 64G. >> >> The above msg comes when the PV guest tries to do WP check. To that end, >> it does set_pte for mapping a (some swapper) temp page in test_wp_bit(): >> >> __set_fixmap(FIX_WP_TEST, __pa_symbol(&swapper_pg_dir), >> PAGE_READONLY); >> boot_cpu_data.wp_works_ok = do_test_wp_bit(); >> clear_fixmap(FIX_WP_TEST); >> >> ... >> /* use writable pagetables */ >> static inline void set_pte(pte_t *ptep, pte_t pte) >> { >> ptep->pte_high = pte.pte_high; >> smp_wmb(); >> ptep->pte_low = pte.pte_low; >> } > > What kernel version is this? > > J While I was debugging 2.6.18-92, I see code is same on 2.6.18-128. The xen version, just in case, 3.3.1. Thanks, Mukesh