Re: linux-next: build failure after merge of the ecryptfs tree

From: Michael Schmitz
Date: Mon May 13 2019 - 21:24:43 EST


Stephen,

I wasn't aware of the other asix module when submitting the phy driver. The phy module gets autoloaded based on the PHY ID, so there's no reason why it couldn't be renamed.

May I suggest ax88796b for the new module name?

Cheers,

    Michael



On 14/05/19 12:56 PM, Stephen Rothwell wrote:
Hi all,

[excessive quoting for new CC's]

On Tue, 14 May 2019 09:40:53 +0900 Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx> wrote:
On Tue, May 14, 2019 at 9:16 AM Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx> wrote:
I don't know why this suddenly appeared after mergeing the ecryptfs tree
since nothin has changed in that tree for some time (and nothing in that
tree seems relevant).

After merging the ecryptfs tree, today's linux-next build (x86_64
allmodconfig) failed like this:

scripts/Makefile.modpost:112: target '.tmp_versions/asix.mod' doesn't match the target pattern
scripts/Makefile.modpost:113: warning: overriding recipe for target '.tmp_versions/asix.mod'
scripts/Makefile.modpost:100: warning: ignoring old recipe for target '.tmp_versions/asix.mod'
scripts/Makefile.modpost:127: target '.tmp_versions/asix.mod' doesn't match the target pattern
scripts/Makefile.modpost:128: warning: overriding recipe for target '.tmp_versions/asix.mod'
scripts/Makefile.modpost:113: warning: ignoring old recipe for target '.tmp_versions/asix.mod'
make[2]: Circular .tmp_versions/asix.mod <- __modpost dependency dropped.
Binary file .tmp_versions/asix.mod matches: No such file or directory
make[2]: *** [scripts/Makefile.modpost:91: __modpost] Error 1
make[1]: *** [Makefile:1290: modules] Error 2

The only clue I can see is that asix.o gets built in two separate
directories (drivers/net/{phy,usb}).
Module name should be unique.

If both are compiled as a module,
they have the same module names:

drivers/net/phy/asix.ko
drivers/net/usb/asix.ko

If you see .tmp_version directory,
you will see asix.mod

Perhaps, one overwrote the other,
or it already got broken somehow.
So, the latter of these drivers (drivers/net/phy/asix.c) was added in
v4.18-rc1 by commit

31dd83b96641 ("net-next: phy: new Asix Electronics PHY driver")

If we can't have 2 modules with the same base name, is it too late to
change its name?

I am sort of suprised that noone else has hit this in the past year.

I have the following files in the object directory:

./.tmp_versions/asix.mod
./drivers/net/usb/asix.ko
./drivers/net/usb/asix.mod.o
./drivers/net/usb/asix.o
./drivers/net/usb/asix_common.o
./drivers/net/usb/asix_devices.o
./drivers/net/usb/.asix.ko.cmd
./drivers/net/usb/.asix.mod.o.cmd
./drivers/net/usb/.asix.o.cmd
./drivers/net/usb/asix.mod.c
./drivers/net/usb/.asix_common.o.cmd
./drivers/net/usb/.asix_devices.o.cmd
./drivers/net/phy/asix.ko
./drivers/net/phy/asix.o
./drivers/net/phy/.asix.ko.cmd
./drivers/net/phy/.asix.mod.o.cmd
./drivers/net/phy/asix.mod.o
./drivers/net/phy/asix.mod.c
./drivers/net/phy/.asix.o.cmd

./.tmp_versions/asix.mod

Looks like this:

------------------------------------------
drivers/net/phy/asix.ko
drivers/net/phy/asix.o


------------------------------------------

What you can't see above are the 256 NUL bytes at the end of the file
(followed by a NL).

This is from a -j 80 build. Surely there is a race condition here if the
file in .tmp_versions is only named for the base name of the module and
we have 2 modules with the same base name.

I removed that file and redid the build and it succeeded.

Mind you, I have no itdea why this file was begin rebuilt, the merge
only touched these files:

fs/ecryptfs/crypto.c
fs/ecryptfs/keystore.c

Puzzled ... :-(