在 2013-8-5,17:10,Gleb Natapov <gleb@xxxxxxxxxx> 写道: > On Mon, Aug 05, 2013 at 04:48:47PM +0800, Arthur Chunqi Li wrote: >> On Mon, Aug 5, 2013 at 4:29 PM, Gleb Natapov <gleb@xxxxxxxxxx> wrote: >>> On Tue, Jul 30, 2013 at 11:41:00PM +0800, Arthur Chunqi Li wrote: >>>> Change "rflags" in "struct regs" to "host_rflags". Remove settings >>>> to GUEST_RFLAGS since GUEST_RFLAGS can be set by vmwrite. Treat >>>> host_rflags as host rflags before and after vmenter. >>> I am not sure the change is for the better. Before the change one could >>> set up rflags for guest environment by setting regs.rflags, no special >>> init function had to be written. I do not see any problem with correct >>> code, except that rflags is not correct on a guest entry, but this >>> should be easy to fix. >> regs.rflags are designed to set guest rflags, but the current >> implementation just use it as host_rflags. > Current implementation uses it to set guest flags at the beginning of > a test. > >> For every VM entry, it will >> load value set by vmcs_write(GUEST_RFLAGS). > Not for every vmentry, only for the first one. Doing it for every > vmentry without saving it first with vmcs_read would been incorrect. > >> Set regs.flags as host >> rflags and then enter VM cannot affect VM's rflags, which is the >> current implementation. > It can, on the first launch. It is easy to add code to exit_handler() to > set current->guest_regs.rflags correctly before calling test's exit handler > and write GUEST_RFLAGS according to current->guest_regs.rflags after > exit handler returns, but as you say below test can do it by itself in > exit handler if it wishes so. > >> Besides, if host want to set/get guest's rflags, it just use >> vmcs_write/read(GUEST_RFLAGS). > True, but to do it at the beginning of the test it will require to write > special init function even if non are needed otherwise. So you are > removing this functionality without clear benefit. True, so it seems better to keep it. However, now it is confused with host_rflags and not correctly set/get when vmentry/vmexit. I will commit another patch to fix both bugs. Arthur > >> Arthur >>> >>>> Besides, add checks to flags after vmenter. >>>> >>>> Signed-off-by: Arthur Chunqi Li <yzt356@xxxxxxxxx> >>>> --- >>>> x86/vmx.c | 11 ++++++----- >>>> x86/vmx.h | 2 +- >>>> 2 files changed, 7 insertions(+), 6 deletions(-) >>>> >>>> diff --git a/x86/vmx.c b/x86/vmx.c >>>> index 7467927..082c3bb 100644 >>>> --- a/x86/vmx.c >>>> +++ b/x86/vmx.c >>>> @@ -481,6 +481,8 @@ static int vmx_run() >>>> "vmresume\n\t" >>>> "2: " >>>> "setbe %0\n\t" >>>> + "jbe vmx_return\n\t" >>>> + "ud2\n\t" >>>> "vmx_return:\n\t" >>>> SAVE_GPR_C >>>> SAVE_RFLAGS >>>> @@ -505,15 +507,15 @@ static int vmx_run() >>>> return 0; >>>> case VMX_TEST_LAUNCH_ERR: >>>> printf("%s : vmlaunch failed.\n", __func__); >>>> - if ((!(regs.rflags & X86_EFLAGS_CF) && !(regs.rflags & X86_EFLAGS_ZF)) >>>> - || ((regs.rflags & X86_EFLAGS_CF) && (regs.rflags & X86_EFLAGS_ZF))) >>>> + if ((!(regs.host_rflags & X86_EFLAGS_CF) && !(regs.host_rflags & X86_EFLAGS_ZF)) >>>> + || ((regs.host_rflags & X86_EFLAGS_CF) && (regs.host_rflags & X86_EFLAGS_ZF))) >>>> printf("\tvmlaunch set wrong flags\n"); >>>> report("test vmlaunch", 0); >>>> break; >>>> case VMX_TEST_RESUME_ERR: >>>> printf("%s : vmresume failed.\n", __func__); >>>> - if ((!(regs.rflags & X86_EFLAGS_CF) && !(regs.rflags & X86_EFLAGS_ZF)) >>>> - || ((regs.rflags & X86_EFLAGS_CF) && (regs.rflags & X86_EFLAGS_ZF))) >>>> + if ((!(regs.host_rflags & X86_EFLAGS_CF) && !(regs.host_rflags & X86_EFLAGS_ZF)) >>>> + || ((regs.host_rflags & X86_EFLAGS_CF) && (regs.host_rflags & X86_EFLAGS_ZF))) >>>> printf("\tvmresume set wrong flags\n"); >>>> report("test vmresume", 0); >>>> break; >>>> @@ -540,7 +542,6 @@ static int test_run(struct vmx_test *test) >>>> test->exits = 0; >>>> current = test; >>>> regs = test->guest_regs; >>>> - vmcs_write(GUEST_RFLAGS, regs.rflags | 0x2); >>>> launched = 0; >>>> printf("\nTest suite : %s\n", test->name); >>>> vmx_run(); >>>> diff --git a/x86/vmx.h b/x86/vmx.h >>>> index 1fb9738..d80e000 100644 >>>> --- a/x86/vmx.h >>>> +++ b/x86/vmx.h >>>> @@ -27,7 +27,7 @@ struct regs { >>>> u64 r13; >>>> u64 r14; >>>> u64 r15; >>>> - u64 rflags; >>>> + u64 host_rflags; >>>> }; >>>> >>>> struct vmx_test { >>>> -- >>>> 1.7.9.5 >>> >>> -- >>> Gleb. > > -- > Gleb. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html