diff options
Diffstat (limited to 'arch/mips')
| -rw-r--r-- | arch/mips/Makefile | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/arch/mips/Makefile b/arch/mips/Makefile index 6ea306b28ae9..8ef9c02747fa 100644 --- a/arch/mips/Makefile +++ b/arch/mips/Makefile @@ -131,6 +131,21 @@ cflags-$(CONFIG_CPU_LITTLE_ENDIAN) += $(shell $(CC) -dumpmachine |grep -q 'mips. cflags-$(CONFIG_SB1XXX_CORELIS) += $(call cc-option,-mno-sched-prolog) \ -fno-omit-frame-pointer + +# Some distribution-specific toolchains might pass the -fstack-check +# option during the build, which adds a simple stack-probe at the beginning +# of every function. This stack probe is to ensure that there is enough +# stack space, else a SEGV is generated. This is not desirable for MIPS +# as kernel stacks are small, placed in unmapped virtual memory, and do not +# grow when overflowed. Especially on SGI IP27 platforms, this check will +# lead to a NULL pointer dereference in _raw_spin_lock_irq. +# +# In disassembly, this stack probe appears at the top of a function as: +# sd zero,<offset>(sp) +# Where <offset> is a negative value. +# +cflags-y += -fno-stack-check + # # CPU-dependent compiler/assembler options for optimization. # |