[Crash-utility] 答复: [External Mail]Re: zram decompress support for gcore/crash-utility

[Dave Anderson]

----- Original Message -----
> I got little problem to compile 32-bit on my x86-64 host..
>  96 /usr/bin/ld: skipping incompatible
>  /usr/lib/gcc/x86_64-linux-gnu/4.8/libgcc.a when searching for -lgcc
>  97 /usr/bin/ld: cannot find -lgcc
>  98 /usr/bin/ld: skipping incompatible
>  /usr/lib/gcc/x86_64-linux-gnu/4.8/libgcc_s.so when searching for -lgcc_s
>  99 /usr/bin/ld: cannot find -lgcc_s
> 
> I think i have fixed the build warning,but failed rebuild in 32-bit since
> above error,please help confirm,and move log to try_zram_decompress,please
> check the attachment.

The patch now compiles OK, but my first simple test shows that something
is obviously wrong with the patch.

Here are a set of user-space addresses that have been swapped out to disk:

  crash> set 1
      PID: 1
  COMMAND: "systemd"
     TASK: ffff92a13a1e8000  [THREAD_INFO: ffff92a13a260000]
      CPU: 2
    STATE: TASK_INTERRUPTIBLE
  crash> vm -p | grep SWAP
  55d917fb5000  SWAP: /dev/dm-2  OFFSET: 55827
  55d917fb7000  SWAP: /dev/dm-2  OFFSET: 55828
  55d917fc2000  SWAP: /dev/dm-2  OFFSET: 121359
  55d917fc6000  SWAP: /dev/dm-2  OFFSET: 88579
  55d917fcb000  SWAP: /dev/dm-2  OFFSET: 88581
  55d917fcc000  SWAP: /dev/dm-2  OFFSET: 88582
  55d917fcd000  SWAP: /dev/dm-2  OFFSET: 88583
  55d917fce000  SWAP: /dev/dm-2  OFFSET: 104963
  55d917fcf000  SWAP: /dev/dm-2  OFFSET: 104964
  ...

Obviously any read of the addresses above should fail, but each
read returns successfully, and each read is screwing up the internal
buffering scheme:

  crash> rd -u 55d917fb5000
      55d917fb5000:  0000000000000000                    ........
  WARNING: malloc/free mismatch (53/54)
  crash> rd -u 55d917fb7000
      55d917fb7000:  0000000000000000                    ........
  WARNING: malloc/free mismatch (53/55)
  crash> rd -u 55d917fc2000
      55d917fc2000:  0000000000000000                    ........
  WARNING: malloc/free mismatch (53/56)
  crash> rd -u 55d917fc6000
      55d917fc6000:  0000000000000000                    ........
  WARNING: malloc/free mismatch (53/57)
  crash>
 
Dave