search for: sh_page_fault

Hi there, I have a question regarding the functionality of x86_emulate_memop (Xen 3.1) or x86_emulate (Xen 3.2) function. This function gets called from sh_page_fault() function which is invoked when Xen receives a page fault. Since I am not clear completely about the emulation operation performed by Xen, I have following questions with a below mentioned scenario? 1) Suppose I have a memory location that I need to protect it from being written by a guest OS. S...

...instruction emulation both in Xen-3.2.1. I am using the following approach: First, I mark a guest page "not present" inside the shadow page table so that I could intercept any operation that involves this page. When the guest tries to access that page, it faults and control goes to Xen (sh_page_fault function). There, I emulate that operation and return the control to guest to execute next instruction. I could get my first part working. In the second part after emulating the instruction inside Xen, I want to perform single-step execution from next instruction onwards so that I could monitor fu...

...crash with a fatal pagefault. However, on inspection of the page tables, the guests'' view of the pagetables was consistent: the page was present. Disabling the out-of-sync optimization made this problem go away. Eventually, I tracked it down to the fault fast path and the OOS code in sh_page_fault(). Here''s what happens: * CPU 0 has a page fault for a PTE in an OOS page that hasn''t been synched yet * CPU 1 has the same page fault (or at least one involving the same L1 page) * CPU 1 enters the fast path * CPU 0 finds the L1 page OOS and starts a resync * CPU 1 finds it'...

...xes this. Signed-off-by: Gianluca Guida <gianluca.guida@eu.citrix.com> diff -r 8848d9e07584 xen/arch/x86/mm/shadow/multi.c --- a/xen/arch/x86/mm/shadow/multi.c Mon Feb 18 21:26:57 2008 +0000 +++ b/xen/arch/x86/mm/shadow/multi.c Tue Feb 19 00:20:00 2008 +0000 @@ -3020,7 +3020,7 @@ static int sh_page_fault(struct vcpu *v, "injection: cr2=%#lx, mfn=%#lx\n", va, mfn_x(gmfn)); sh_remove_shadows(v, gmfn, 0 /* thorough */, 1 /* must succeed */); - goto done; + return EXCRET_fault_fixed; } } _________...

In sh_page_fault(), there are some code like following, why we think it is mmio only when paging_vcpu_mode_translate(v)? Thanks Yunhong Jiang /* What mfn is the guest trying to access? */ gfn = guest_l1e_get_gfn(gw.eff_l1e); gmfn = vcpu_gfn_to_mfn(v, gfn); mmio = (is_hvm_domain(d) &am...

Is there any trouble with mailing list? I didn''t see my mail sent back after almost 8hrs. :-( Thanks, Kevin -----Original Message----- From: Tian, Kevin Sent: 2008年2月22日 10:33 To: ''Tim Deegan'' Cc: xen-devel@lists.xensource.com Subject: [PATCH][UPDATE]Remove lock on guest table walk >From: Tim Deegan >Sent: 2008年2月21日 22:13 >Hi, > >So, the idea seems

...+ sh_map_domain_page(gmfn)); pg = mfn_to_page(gmfn); diff -r bfd1157dd315 xen/arch/x86/mm/shadow/multi.c --- a/xen/arch/x86/mm/shadow/multi.c Thu Sep 11 08:06:48 2008 +0900 +++ b/xen/arch/x86/mm/shadow/multi.c Thu Sep 11 09:49:09 2008 +0900 @@ -3041,9 +3041,14 @@ static int sh_page_fault(struct vcpu *v, int fast_emul = 0; #endif +#ifdef __x86_64__ SHADOW_PRINTK("d:v=%u:%u va=%#lx err=%u, rip=%lx\n", v->domain->domain_id, v->vcpu_id, va, regs->error_code, regs->rip); +#elif defined(__i386__) + SHADOW_PRINT...

Hi All, I have several questions about log dirty mode during live migration. For my understanding, each time after XEN_DOMCTL_SHADOW_OP_CLEAN or XEN_DOMCTL_SHADOW_OP_PEEK operation, all the pages are set as read only. The following memory accesses to the memory pages will cause page fault (permission conflict) then using page_mark_dirty function to set the dirty bitmap. However, after I read

Hi, I have a question about memory page tables in Xen. As far as I understood, every modification to page table will go through Xen(hypervisor). Is it so that all page tables are actually allocated in Xen(hypervisor) instead of guest OS(domain)? Also, is it the case that Xen(hypervisor) needs to maintain a page table for each process running in every domain? Thanks Haifeng