[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [RFC][PATCH 07/16 v6] target-i386: Add API to add extra
From: |
Wen Congyang |
Subject: |
Re: [Qemu-devel] [RFC][PATCH 07/16 v6] target-i386: Add API to add extra memory mapping |
Date: |
Wed, 15 Feb 2012 17:44:02 +0800 |
User-agent: |
Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.9) Gecko/20100413 Fedora/3.0.4-2.fc13 Thunderbird/3.0.4 |
At 02/15/2012 05:21 PM, Jan Kiszka Wrote:
> On 2012-02-15 06:19, Wen Congyang wrote:
>> At 02/15/2012 01:35 AM, Jan Kiszka Wrote:
>>> On 2012-02-09 04:24, Wen Congyang wrote:
>>>> Crash needs extra memory mapping to determine phys_base.
>>>>
>>>> Signed-off-by: Wen Congyang <address@hidden>
>>>> ---
>>>> cpu-all.h | 2 ++
>>>> target-i386/arch-dump.c | 43 +++++++++++++++++++++++++++++++++++++++++++
>>>> 2 files changed, 45 insertions(+), 0 deletions(-)
>>>>
>>>> diff --git a/cpu-all.h b/cpu-all.h
>>>> index efb5ba3..290c43a 100644
>>>> --- a/cpu-all.h
>>>> +++ b/cpu-all.h
>>>> @@ -530,10 +530,12 @@ int cpu_write_elf64_note(int fd, CPUState *env, int
>>>> cpuid,
>>>> target_phys_addr_t *offset);
>>>> int cpu_write_elf32_note(int fd, CPUState *env, int cpuid,
>>>> target_phys_addr_t *offset);
>>>> +int cpu_add_extra_memory_mapping(MemoryMappingList *list);
>>>> #else
>>>> #define cpu_get_memory_mapping(list, env)
>>>> #define cpu_write_elf64_note(fd, env, cpuid, offset) ({ -1; })
>>>> #define cpu_write_elf32_note(fd, env, cpuid, offset) ({ -1; })
>>>> +#define cpu_add_extra_memory_mapping(list) ({ 0; })
>>>> #endif
>>>>
>>>> #endif /* CPU_ALL_H */
>>>> diff --git a/target-i386/arch-dump.c b/target-i386/arch-dump.c
>>>> index 4c0ff77..d96f6ae 100644
>>>> --- a/target-i386/arch-dump.c
>>>> +++ b/target-i386/arch-dump.c
>>>> @@ -495,3 +495,46 @@ int cpu_write_elf32_note(int fd, CPUState *env, int
>>>> cpuid,
>>>> {
>>>> return x86_write_elf32_note(fd, env, cpuid, offset);
>>>> }
>>>> +
>>>> +/* This function is copied from crash */
>>>
>>> And what does it do there and here? I suppose it is Linux-specific - any
>>> version? This should be documented and encoded in the function name.
>>>
>>>> +static target_ulong get_phys_base_addr(CPUState *env, target_ulong
>>>> *base_vaddr)
>>>> +{
>>>> + int i;
>>>> + target_ulong kernel_base = -1;
>>>> + target_ulong last, mask;
>>>> +
>>>> + for (i = 30, last = -1; (kernel_base == -1) && (i >= 20); i--) {
>>>> + mask = ~((1LL << i) - 1);
>>>> + *base_vaddr = env->idt.base & mask;
>>>> + if (*base_vaddr == last) {
>>>> + continue;
>>>> + }
>>>> +
>>>> + kernel_base = cpu_get_phys_page_debug(env, *base_vaddr);
>>>> + last = *base_vaddr;
>>>> + }
>>>> +
>>>> + return kernel_base;
>>>> +}
>>>> +
>>>> +int cpu_add_extra_memory_mapping(MemoryMappingList *list)
>>>
>>> Again, what does "extra" mean? Probably guest-specific, no?
>>
>> crash will calculate the phys_base according to the virtual address and
>> physical
>> address stored in the PT_LOAD.
>
> Crash is a Linux-only tool, dump must not be restricted to that guest -
> but could contain transparent extensions of the file format if needed.
>
>>
>> If the vmcore is generated by 'virsh dump'(use migration to implement
>> dumping),
>> crash calculates the phys_base according to idt.base. The function
>> get_phys_base_addr()
>> uses the same way to calculates the phys_base.
>
> Hmm, where are those special registers (idt, gdt, tr etc.) stored in the
> vmcore file, BTW?
'virsh dump' uses mirgation to implement dumping now. So the vmcore has all
registers.
>
>>
>> I think crash may work without this. I will verify it.
I want to modify crash to make it work without this. I am discussing it
with Dave Anderson in crash community now.
>
> Does gdb require this?
IIRC, the answer is no.
Thanks
Wen Congyang
>
> Jan
>
- Re: [Qemu-devel] [RFC][PATCH 05/16 v6] Add API to get memory mapping, (continued)
[Qemu-devel] [RFC][PATCH 06/16 v6] target-i386: Add API to write elf notes to core file, Wen Congyang, 2012/02/08
[Qemu-devel] [RFC][PATCH 07/16 v6] target-i386: Add API to add extra memory mapping, Wen Congyang, 2012/02/08
- Re: [Qemu-devel] [RFC][PATCH 07/16 v6] target-i386: Add API to add extra memory mapping, Jan Kiszka, 2012/02/14
- Re: [Qemu-devel] [RFC][PATCH 07/16 v6] target-i386: Add API to add extra memory mapping, Wen Congyang, 2012/02/15
- Re: [Qemu-devel] [RFC][PATCH 07/16 v6] target-i386: Add API to add extra memory mapping, Jan Kiszka, 2012/02/15
- Re: [Qemu-devel] [RFC][PATCH 07/16 v6] target-i386: Add API to add extra memory mapping,
Wen Congyang <=
- Re: [Qemu-devel] [RFC][PATCH 07/16 v6] target-i386: Add API to add extra memory mapping, Jan Kiszka, 2012/02/15
- Re: [Qemu-devel] [RFC][PATCH 07/16 v6] target-i386: Add API to add extra memory mapping, Wen Congyang, 2012/02/17
- Re: [Qemu-devel] [RFC][PATCH 07/16 v6] target-i386: Add API to add extra memory mapping, HATAYAMA Daisuke, 2012/02/17
[Qemu-devel] [RFC][PATCH 08/16 v6] target-i386: add API to get dump info, Wen Congyang, 2012/02/08
Re: [Qemu-devel] [RFC][PATCH 08/16 v6] target-i386: add API to get dump info, Peter Maydell, 2012/02/15