Re: depmod gets stuck in symlink cycle in arch/arm/boot/dts/include

[Yauheni Kaliuta]

Hi, Omar!

>>>>> On Fri, 12 May 2017 15:23:07 -0700, Omar Sandoval  wrote:

 > Hi,
 > Linux kernel commit 4027494ae6e3 ("ARM: dts: add arm/arm64 include
 > symlinks") introduced a couple of symlink cycles:

 > $ ls -al arch/arm{,64}/boot/dts/include
 > arch/arm64/boot/dts/include:
 > total 12
 > drwxr-xr-x 1 osandov users  38 May 11 14:01 .
 > drwxr-xr-x 1 osandov users 320 Jan 25 20:44 ..
 > lrwxrwxrwx 1 osandov users  24 May 11 14:01 arm -> ../../../../arm/boot/dts
 > lrwxrwxrwx 1 osandov users   2 May 11 14:01 arm64 -> ..
 > lrwxrwxrwx 1 osandov users 34 Nov 23 12:07 dt-bindings ->
 > ../../../../../include/dt-bindings

 > arch/arm/boot/dts/include:
 > total 12
 > drwxr-xr-x 1 osandov users    38 May 11 14:01 .
 > drwxr-xr-x 1 osandov users 63102 May 11 14:01 ..
 > lrwxrwxrwx 1 osandov users     2 May 11 14:01 arm -> ..
 > lrwxrwxrwx 1 osandov users    26 May 11 14:01 arm64 -> ../../../../arm64/boot/dts
 > lrwxrwxrwx 1 osandov users 34 Nov 23 12:07 dt-bindings ->
 > ../../../../../include/dt-bindings

 > On my system, /lib/modules/$(uname -r)/kernel is a symlink to
 > /lib/modules/$(uname -r)/build, which is my built linux.git. depmod
 > doesn't like these symlink cycles and ends up in an infinite loop.

 > Maybe I shouldn't be symlinking kernel to build like this, but depmod
 > shouldn't be getting stuck like this either. I wonder if anything else
 > is going to barf on these symlink cycles, too.

depmod checks for special names "build" and "source" to skip them.

I wonder if it worth to implement full symlink loop check.

-- 
WBR,
Yauheni Kaliuta