Buildroot Config Option for applying custom patch - buildroot

Question

I am new to buildroot and working to build Linaro with buildroot ..I have multiple fragment kernel config files and specified that in buildroot defconfig.
I have specified a custom kernel patches directory with BR2_LINUX_PATCH_DIR .
I dont have some of the config flags not set which are supposed to be there in the .config files..so i suspect that the Patches are applied successfully..so i tried giving a non existing location as Linux Patch dir and it does not give any error..
Is there anything other than giving value to BR2_LINUX_PATCH_DIR and what should be the format of the dir structure...in buildroot manual it says it should be
Package_name/patch name..For linux what should be the package name? It should be the same with which linux dir is created.for example for me it is linux-custom
Plz suggest and guide me in this.
Thanks in Advance

Answer 1

The option is named BR2_LINUX_KERNEL_PATCH, there is nothing named BR2_LINUX_PATCH_DIR. It applies all patches listed in this option (if those are files), or all files named *.patch if what's given in this option is a directory. See the code in linux/linux.mk:
define LINUX_APPLY_LOCAL_PATCHES
for p in $(filter-out ftp://% http://% https://%,$(LINUX_PATCHES)) ; do \
if test -d $$p ; then \
$(APPLY_PATCHES) $(#D) $$p \*.patch || exit 1 ; \
else \
$(APPLY_PATCHES) $(#D) `dirname $$p` `basename $$p` || exit 1; \
fi \
done
endef
Also, I would recommend that you watch the output of Buildroot: it shows everything it is doing, especially it lists the patches it applied. Look at the line >>> linux .... Patching, which is the marker for the beginning of the patching step of the linux package.