kfence: limit currently covered allocations when pool nearly full

[platform/kernel/linux-rpi.git] / Makefile

diff --git a/Makefile b/Makefile
index 7b74223..d09ac84 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -2,8 +2,8 @@
 VERSION = 5
 PATCHLEVEL = 15
 SUBLEVEL = 0
-EXTRAVERSION = -rc4
-NAME = Opossums on Parade
+EXTRAVERSION =
+NAME = Trick or Treat
 
 # *DOCUMENTATION*
 # To see a list of typical targets execute "make help"
@@ -1008,6 +1008,21 @@ ifdef CONFIG_CC_IS_GCC
 KBUILD_CFLAGS += -Wno-maybe-uninitialized
 endif
 
+ifdef CONFIG_CC_IS_GCC
+# The allocators already balk at large sizes, so silence the compiler
+# warnings for bounds checks involving those possible values. While
+# -Wno-alloc-size-larger-than would normally be used here, earlier versions
+# of gcc (<9.1) weirdly don't handle the option correctly when _other_
+# warnings are produced (?!). Using -Walloc-size-larger-than=SIZE_MAX
+# doesn't work (as it is documented to), silently resolving to "0" prior to
+# version 9.1 (and producing an error more recently). Numeric values larger
+# than PTRDIFF_MAX also don't work prior to version 9.1, which are silently
+# ignored, continuing to default to PTRDIFF_MAX. So, left with no other
+# choice, we must perform a versioned check to disable this warning.
+# https://lore.kernel.org/lkml/20210824115859.187f272f@canb.auug.org.au
+KBUILD_CFLAGS += $(call cc-ifversion, -ge, 0901, -Wno-alloc-size-larger-than)
+endif
+
 # disable invalid "can't wrap" optimizations for signed / pointers
 KBUILD_CFLAGS  += -fno-strict-overflow