Bug#365363: multipath fails when cheap USB disk present

[Christophe Varoqui]

Michael Shuey a écrit :
> Package: multipath-tools
> Version: 0.4.7-1
>
> The multipath tool dies (exit code is 1) whenever I have a particular cheap 
> USB drive plugged in.  Digging a bit with strace shows:
>
> <snip>
> open("/sys/block/sdx/dev", O_RDONLY)    = 26
> read(26, "65:112\n", 4096)              = 7
> close(26)                               = 0
> stat64("/sys/block/sdx/size", {st_mode=S_IFREG|0444, st_size=4096, ...}) = 0
> open("/sys/block/sdx/size", O_RDONLY)   = 26
> read(26, "160086528\n", 4096)           = 10
> close(26)                               = 0
> stat64("/sys/block/sdx/device/vendor", {st_mode=S_IFREG|0444, 
> st_size=4096, ...}) = 0
> open("/sys/block/sdx/device/vendor", O_RDONLY) = 26
> read(26, "Maxtor 4\n", 4096)            = 9
> close(26)                               = 0
> stat64("/sys/block/sdx/device/model", {st_mode=S_IFREG|0444, 
> st_size=4096, ...}) = 0
> open("/sys/block/sdx/device/model", O_RDONLY) = 26
> read(26, "D080H4          \n", 4096)    = 17
> close(26)                               = 0
> stat64("/sys/block/sdx/device/rev", {st_mode=S_IFREG|0444, 
> st_size=4096, ...}) = 0
> open("/sys/block/sdx/device/rev", O_RDONLY) = 26
> read(26, "\n", 4096)                    = 1
> close(26)                               = 0
> close(4)                                = 0
> <snip>
>
> Sure enough, /dev/sdx is a cheapo USB disk enclose, and sysfs doesn't report 
> a revision number for the drive.
>
> If I unplug the USB disk, multipath works fine.  My guess is that either 
> multipath itself, or maybe libsysfs, can't handle the existence of an 
> empty /sys/block/sdx/device/rev.  If it matters, I'm using libsysfs2 
> 2.0.0-6.
>
>   
I'm not sure the empty rev string is the problem here.
Can you send a "multipaht -v4" ouput and ideally a gdb "backtrace full" ?

Thanks.