The patch titled Subject: s390/vmlogrdr: remove function pointer cast has been added to the -mm mm-nonmm-unstable branch. Its filename is s390-vmlogrdr-remove-function-pointer-cast.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/s390-vmlogrdr-remove-function-pointer-cast.patch This patch will later appear in the mm-nonmm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Nathan Chancellor <nathan@xxxxxxxxxx> Subject: s390/vmlogrdr: remove function pointer cast Date: Wed, 17 Apr 2024 11:24:35 -0700 Patch series "drivers/s390: Fix instances of -Wcast-function-type-strict". This series resolves the instances of -Wcast-function-type-strict that show up in my s390 builds on -next, which has this warning enabled by default. This patch (of 3): Clang warns (or errors with CONFIG_WERROR) after enabling -Wcast-function-type-strict by default: drivers/s390/char/vmlogrdr.c:746:18: error: cast from 'void (*)(const void *)' to 'void (*)(struct device *)' converts to incompatible function type [-Werror,-Wcast-function-type-strict] 746 | dev->release = (void (*)(struct device *))kfree; | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 1 error generated. Add a standalone function to fix the warning properly, which addresses the root of the warning that these casts are not safe for kCFI. The comment is not really relevant after this change, so remove it. Link: https://lkml.kernel.org/r/20240417-s390-drivers-fix-cast-function-type-v1-0-fd048c9903b0@xxxxxxxxxx Link: https://lkml.kernel.org/r/20240417-s390-drivers-fix-cast-function-type-v1-1-fd048c9903b0@xxxxxxxxxx Signed-off-by: Nathan Chancellor <nathan@xxxxxxxxxx> Reviewed-by: Arnd Bergmann <arnd@xxxxxxxx> Cc: Alexander Gordeev <agordeev@xxxxxxxxxxxxx> Cc: Alexandra Winter <wintera@xxxxxxxxxxxxx> Cc: Christian Borntraeger <borntraeger@xxxxxxxxxxxxx> Cc: Heiko Carstens <hca@xxxxxxxxxxxxx> Cc: Sven Schnelle <svens@xxxxxxxxxxxxx> Cc: Thorsten Winkler <twinkler@xxxxxxxxxxxxx> Cc: Vasily Gorbik <gor@xxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- drivers/s390/char/vmlogrdr.c | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) --- a/drivers/s390/char/vmlogrdr.c~s390-vmlogrdr-remove-function-pointer-cast +++ a/drivers/s390/char/vmlogrdr.c @@ -722,6 +722,10 @@ static void vmlogrdr_unregister_driver(v iucv_unregister(&vmlogrdr_iucv_handler, 1); } +static void vmlogrdr_free_dev(struct device *dev) +{ + kfree(dev); +} static int vmlogrdr_register_device(struct vmlogrdr_priv_t *priv) { @@ -736,14 +740,7 @@ static int vmlogrdr_register_device(stru dev->driver = &vmlogrdr_driver; dev->groups = vmlogrdr_attr_groups; dev_set_drvdata(dev, priv); - /* - * The release function could be called after the - * module has been unloaded. It's _only_ task is to - * free the struct. Therefore, we specify kfree() - * directly here. (Probably a little bit obfuscating - * but legitime ...). - */ - dev->release = (void (*)(struct device *))kfree; + dev->release = vmlogrdr_free_dev; } else return -ENOMEM; ret = device_register(dev); _ Patches currently in -mm which might be from nathan@xxxxxxxxxx are s390-vmlogrdr-remove-function-pointer-cast.patch s390-smsgiucv_app-remove-function-pointer-cast.patch s390-netiucv-remove-function-pointer-cast.patch