On 04/14/2012 03:44 PM, 陳韋任 wrote:
>> I've made a test from the grub multiboot sample, you may find it here:
>> http://jcmvbkbc.spb.ru/git/?p=dumb/qemu-test-kernel.git;a=summary
>>
>> With it I see that an attempt to execute a TB that spans two pages causes
>> an exception when the second page is
> I've made a test from the grub multiboot sample, you may find it here:
> http://jcmvbkbc.spb.ru/git/?p=dumb/qemu-test-kernel.git;a=summary
>
> With it I see that an attempt to execute a TB that spans two pages causes
> an exception when the second page is unmapped. It happens because both
> tlb_f
>> Doesn't a tb spanning guest pages have above problem? I mean what if the
>> guest page 2 is changed? In this case, the execution flow jump from tb.a to
>> tb.b. It seems it may have the same problem as above to me.
>
> I agree. I see that only i386 and m68k TBs may cross page boundary.
> Maybe
On Thu, Apr 12, 2012 at 1:04 AM, Peter Maydell wrote:
> On 11 April 2012 22:00, Max Filippov wrote:
>> 陳韋任 :
>>> Doesn't a tb spanning guest pages have above problem? I mean what if the
>>> guest page 2 is changed? In this case, the execution flow jump from tb.a to
>>> tb.b. It seems it may have
On 11 April 2012 22:00, Max Filippov wrote:
> 陳韋任 :
>> Doesn't a tb spanning guest pages have above problem? I mean what if the
>> guest page 2 is changed? In this case, the execution flow jump from tb.a to
>> tb.b. It seems it may have the same problem as above to me.
>
> I agree. I see that onl
>> s->pc is updated each time a byte of code is fetched, when an instruction
>> is fully decoded s->pc points to the first byte of the next instruction. I
>> see
>> that it only makes difference when a branching instruction ends exactly at
>> a page boundary. In this case (s->pc - 1) prevents from
> s->pc is updated each time a byte of code is fetched, when an instruction
> is fully decoded s->pc points to the first byte of the next instruction. I see
> that it only makes difference when a branching instruction ends exactly at
> a page boundary. In this case (s->pc - 1) prevents from linking
> Could someone help me to confirm that I understand how the QEMU cross page
> boundary checking correctly or not? Below is the source code I am looking at,
>
> static inline void gen_goto_tb(DisasContext *s, int tb_num, target_ulong eip)
> {
>
> if ((pc & TARGET_PAGE_MASK) == (tb->pc & TARGET_
Hi all,
Could someone help me to confirm that I understand how the QEMU cross page
boundary checking correctly or not? Below is the source code I am looking at,
static inline void gen_goto_tb(DisasContext *s, int tb_num, target_ulong eip)
{
if ((pc & TARGET_PAGE_MASK) == (tb->pc & TARGET_
