[Crash-utility] ARM support for CONFIG_SPARSEMEM:(wasRe:DDimage)

Tue Jun 21 03:51:48 UTC 2011

>>>But it only happens when I use KDUMP format instead of NETDUMP_ELF32.
I cannot reconfirm this. Please forget about it.
I forgot to mention one thing.  I had to remove the following line from symbol.c as my target is non-SMP
1413: 	lm->mod_percpu = ULONG(modbuf + OFFSET(module_percpu));
I hope you will find a better way.

Best Regards,

Takuo

>Thank you forc crash-5.1.6.
>
>>But I'm thinking that if the VTOP/PTOV issue is resolved, then you won't
>>see that readmem() error in FILL_PTBL(), because the address that was
>>failing was generated by PTOV():
>>
>>        /*
>>         * pte_offset_map(pmd, vaddr)
>>         */
>>        page_table = (ulong *)PTOV(pmd_page_addr(pmd_pte)) + PTE_OFFSET(vaddr);
>>
>>        FILL_PTBL(PAGEBASE(page_table), KVADDR, PAGESIZE());
>
>
>With the modification of VTOP/PTOV, crash-5.1.6 recognizes "page table" of CONFIG_SPARSEMEM vmcore file and init_module_unwind_tables succeeds and backtrace  command without -t option works now.  But it only happens when I use KDUMP format instead of NETDUMP_ELF32. (please remember I created vmcore file from raw memory images).
>Program Headers:
>  Type           Offset   VirtAddr   PhysAddr   FileSiz MemSiz  Flg Align
>  NOTE           0x000094 0x00000000 0x00000000 0x00000 0x00000     0
>  LOAD           0x000094 0xc0000000 0x00200000 0xfe00000 0xfe00000 RWE 0
>  LOAD           0xfe00094 0xd0000000 0x40000000 0x10000000 0x10000000 RWE 0
>I did not noticed that read_netdump() does not support multiple PT_LOADs for NETDUMP_ELF32 dump file format until yesterday.
>
>It seems to me that VTOP/PTOV calculation fomula can be obtained from vmcore file. Am I wrong?
>
>Best Regards,
>
>Takuo
>
>>
>>
>>----- Original Message -----
>>> Dave, Mika,
>>> memory.h I am using is probably the same as this,
>>> https://www.codeaurora.org/gitweb/quic/la/?p=kernel/msm.git;a=blob;f=arch/arm/mach-msm/include/mach/memory.h;h=afe6051b9826d788849aafa52b55b3760b6cf1ec;hb=debd216b762a87da0faf0eb4f991ed10c7a052cc
>>> 
>>> 19 /* physical offset of RAM */
>>> 20 #define PHYS_OFFSET UL(CONFIG_PHYS_OFFSET) <-- 0x00200000
>>> 21
>>> 22 #define MAX_PHYSMEM_BITS 32
>>> 23 #define SECTION_SIZE_BITS 28
>>> 24
>>> 25 /* Certain configurations of MSM7x30 have multiple memory banks.
>>> 26 * One or more of these banks can contain holes in the memory map as well.
>>> 27 * These macros define appropriate conversion routines between the physical
>>> 28 * and virtual address domains for supporting these configurations using
>>> 29 * SPARSEMEM and a 3G/1G VM split.
>>> 30 */
>>> 31
>>> 32 #if defined(CONFIG_ARCH_MSM7X30)
>>> 33
>>> 34 #define EBI0_PHYS_OFFSET PHYS_OFFSET
>>> 35 #define EBI0_PAGE_OFFSET PAGE_OFFSET
>>> 36 #define EBI0_SIZE 0x10000000
>>> 37
>>> 38 #define EBI1_PHYS_OFFSET 0x40000000
>>> 39 #define EBI1_PAGE_OFFSET (EBI0_PAGE_OFFSET + EBI0_SIZE)
>>> 40
>>> 41 #if (defined(CONFIG_SPARSEMEM) && defined(CONFIG_VMSPLIT_3G))
>>> 42
>>> 43 #define __phys_to_virt(phys) \
>>> 44 ((phys) >= EBI1_PHYS_OFFSET ? \
>>> 45 (phys) - EBI1_PHYS_OFFSET + EBI1_PAGE_OFFSET : \
>>> 46 (phys) - EBI0_PHYS_OFFSET + EBI0_PAGE_OFFSET)
>>> 47
>>> 48 #define __virt_to_phys(virt) \
>>> 49 ((virt) >= EBI1_PAGE_OFFSET ? \
>>> 50 (virt) - EBI1_PAGE_OFFSET + EBI1_PHYS_OFFSET : \
>>> 51 (virt) - EBI0_PAGE_OFFSET + EBI0_PHYS_OFFSET)
>>> 52
>>> 53 #endif
>>> 54
>>> 55 #endif
>>> 
>>> 
>>> So my previous description of actual memory mapping was not correct.
>>> The correct description is,
>>> Virtual 0xc0000000-0xcfdfffff -> Physical 0x00200000-0x0fffffff
>>> and
>>> Virtual 0xd0000000-0xdfffffff -> Physical 0x40000000-0x4fffffff
>>> Tomorrow I will check if vmcore with the following header is
>>> recognized by crash.
>>> Type Offset VirtAddr PhysAddr FileSiz MemSiz Flg Align
>>> NOTE 0x000094 0x00000000 0x00000000 0x00000 0x00000 0
>>> LOAD 0x000094 0xc0000000 0x00200000 0x0fe00000 0x0fe00000 RWE
>>> LOAD 0x0fe00094 0xc0000000 0x40000000 0x10000000 0x10000000 RWE
>>
>>Shouldn't the second PT_LOAD segment have a p_vaddr of 0xc0000000?
>>
>>Although, in the case of ARM, I believe that the p_vaddr field
>>is not used by the crash utility, as it is only interested in the
>>p_paddr and p_memsz/p_filesz fields.  But I presume you meant 
>>0xd0000000 for the second one.
>>
>>> 
>>> And I guess VTOP/PTOV needs modification in accordance with
>>> __phys_to_virt and __virt_to_phys.
>>
>>Right...
>>
>>Ultimately it will be advisable to extract the ARM VTOP() and PTOV()
>>macros into machine-dependent functions, i.e., similar to the X86_64
>>and IA64 architectures.  And in those functions, intelligence will
>>have to be applied to determine how to handle the various ARM types.
>>
>>> 
>>> For your information,
>>> The vmcore file with the following header is recognized by crash and
>>> many commands works fine,
>>> Type Offset VirtAddr PhysAddr FileSiz MemSiz Flg Align
>>> NOTE 0x000074 0x00000000 0x00000000 0x00000 0x00000 0
>>> LOAD 0x000074 0xc0000000 0x00000000 0x20000000 0x20000000 RWE
>>> if the patches for unwind_arm.c, arm.c and defs.h posted in this ML
>>> thread applied and readmem error_handle for FILL_PTBL is change to
>>> RETURN_ON_ERROR.
>>> Without the last modification above crash exits when readmem fails at
>>> FILL_PTBL before reaching the first prompt.
>>
>>But I'm thinking that if the VTOP/PTOV issue is resolved, then you won't
>>see that readmem() error in FILL_PTBL(), because the address that was
>>failing was generated by PTOV():
>>
>>        /*
>>         * pte_offset_map(pmd, vaddr)
>>         */
>>        page_table = (ulong *)PTOV(pmd_page_addr(pmd_pte)) + PTE_OFFSET(vaddr);
>>
>>        FILL_PTBL(PAGEBASE(page_table), KVADDR, PAGESIZE());
>>
>>Dave
>> 
>>
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>>
>