similar to: Query regarding x86_emulate_memop() function

Hi all, I am trying to perform single-stepping and 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

With the x86 instruction emulator no pretty complete, I''d like to re-submit this patch to support cmpxchg16b on x86-64 and at once rename the underlying emulator callback function pointer (making clear that if implemented, it is to operate on two longs rather than two 32-bit values). At the same time it fixes an apparently wrong emulator context initialization in the shadow code.

Hi, Keir, This patch is to fix the problem of Linux guest installation failure and Windows 2000 boot failure.       In the early code, we use vmx_vmexit_handler() -> vmx_io_instruction() function to emulate I/O instructions. But now, we use vmx_vmexit_handler() -> handle_mmio -> hvm_emulate_one() -> x86_emulate() to emulate I/O instructions. Also nowadays, the realmode

> Hmmm... wouldn''t it be nice if we didn''t have a bespoke, > buggy & incomplete emulator for hvm mmio. ;-) In the process of solving this one, I''ve got to (another) of the blocking points... At the moment, we translate the virtual address from the guest in the page-fault-handler to guest physical address via the gva_to_gpa() function in svm.c/vmx.c:

We saw these issues in recent ChangeSet: 1. Reboot fail in Guest OS: Reboot in guest will close current qemu windows but does not create a new qemu window to restart 32bit HV/xen0: 2. 4 LTP math cases(float_bessel, float_exp_log, float_power and float_trigo) sometime fail. (775) 3. Kernel build in VMX may meet kernel panic. It complains like: "<0> Kernel panic - not syncing:

- we used the C4/C5 (first prefix) byte instead of the apparent ModR/M one as the second prefix byte - early decoding normalized vex.reg, thus corrupting it for the main consumer (copy_REX_VEX()), resulting in #UD on the two-operand instructions we emulate Also add respective test cases to the testing utility plus - fix get_fpu() (the fall-through order was inverted) - add cpu_has_avx2,

All, in the light of erratum #573 I''m wondering if we need to tweak or conditionally suppress fsincos emulation. The question is whether there is any possibility for getting the emulator to hit this instruction on AMD (as no real mode emulation ought to be taking place there), i.e. whether there are places where emulation gets continued eagerly in anticipation of the need for emulation

Hi all, In arch/x86/x86_emulate.c: x86_emulate(): 1716 case 0xfe: /* Grp4 */ 1717 generate_exception_if((m odrm_reg & 7) >= 2, EXC_UD); 1718 case 0xff: /* Grp5 */ 1719 switch ( modrm_reg & 7 ) 1720 { 1721 case 0: /* inc */ 1722 emulate_1op("inc", dst, _regs.eflags); 1723 break; 1724

I do recieve this error when building xen-unstable tree. gcc -O2 -fomit-frame-pointer -m32 -march=i686 -DNDEBUG -fno-strict-aliasing -std=gnu99 -Wall -Wstrict-prototypes -Wno-unused-value -Wdeclaration-after-statement -DVMXASSIST -nostdinc -fno-builtin -fno-common -iwithprefix include -Werror -Wno-pointer-arith -pipe -I/home/xen-unstable.hg/xen/include

Add MOVSX instr support to VMX MMIO decoder. Signed-off-by: Xin Li <xin.b.li@intel.com> _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel

Patrick, there following patches fix xenpaging for me. Granttable handling is incomplete. If a page is gone, a GNTST_eagain should be returned to the caller to inidcate the hypercall has to be retried after a while, until the page is available again. Please review. Olaf _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com

This set of patches converts the way frames gets created from using PUSHes/POPs to using MOVes, thus allowing (in certain cases) to avoid saving/restoring part of the register set. While the place where the (small) win from this comes from varies between CPUs, the net effect is a 1 to 2% reduction on a combined interruption entry and exit when the full state save can be avoided. 1: use MOV

Hi guys, At a loss trying to figure why if (has_eflag(X86_EFLAGS_ID)) returns false in my HVM domU. Standard function has_eflag() in cpucheck.c running in real mode. Works fine on PV dom0, but fails when guest is booting on my hybrid dom0. LMK if any ideas. I''ll keep digging in the manuals, but nothing so far. thanks, Mukesh

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

Xen is compiled with no -O gcc option, meaning no optimization, and the compiler does the safest thing imaginable. This means that if a function, say vmx_world_save(), calls the same inline a bazillion times, the stack will have one block of local variables for each invocation of that function! Xen really should not be doing this. We could either uninline some of these functions, or try gcc -O2

We''ve got reports of that change causing HVM data corruption issues. While I can''t see what''s wrong with the patch, I''d suggest at least reverting it from the 3.3 tree (which is what our code is based upon) for the time being. Jan _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com

Hi all, I am having confusion regarding the way a newly created domain is allocated vcpu. Initially during dom0 creation alloc_vcpu is called to create vcpu structs for all the available cpu''s and assigned to dom0. But its not the case for domU creation. 1. So how will dom0 relinquish/share vcpu to/with a newly created domU. Does this happen as part of the shared_info page mapping??

The attached patch fixes the save/restore issue seen with 32bit Windows guest VMs. The root cause is that current Xen doesn''t intercept SYSENTER-related MSRs for 32bit guest VMs. As a result, the guest_sysenter_xxx fields contain incorrect values and shouldn''t be used for save/restore. This patch checks the LMA bit of EFER register in the save/restore code path. Please apply it

Commit 86781624 ("x86_emulate: PUSH <mem> must read source operand just once") corrected the operands of those of the operations of opcode extension group 5 that only read memory from SrcMem to DstMem, but failed to also switch the use of "dst" here to "src". Reported-by: Anthony Perard <anthony.perard@citrix.com> Signed-off-by: Jan Beulich

We recently observed a problem with Solaris HVM domains. The bug was seen was seen with a higher number of VCPUs (3 or more), and always had the same pattern: some memory was allocated in the guest, but the first reference caused it to crash with a fatal pagefault. However, on inspection of the page tables, the guests'' view of the pagetables was consistent: the page was present.