uapi/auxvec: Define the aux vector AT_MINSIGSTKSZ

mainline inclusion
from mainline-v5.14-rc1
commit 7cd60e43
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit 7cd60e43 uapi/auxvec: Define the aux vector AT_MINSIGSTKSZ.

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

Define AT_MINSIGSTKSZ in the generic uapi header. It is already used
as generic ABI in glibc's generic elf.h, and this define will prevent
future namespace conflicts. In particular, x86 is also using this
generic definition.
Signed-off-by: NChang S. Bae <chang.seok.bae@intel.com>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Reviewed-by: NLen Brown <len.brown@intel.com>
Acked-by: NThomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20210518200320.17239-2-chang.seok.bae@intel.comSigned-off-by: NLin Wang <lin.x.wang@intel.com>

include/uapi/linux/auxvec.h

@@ -33,5 +33,8 @@
 
 #define AT_EXECFN  31	/* filename of program */
 
+#ifndef AT_MINSIGSTKSZ
+#define AT_MINSIGSTKSZ	51	/* minimal stack size for signal delivery */
+#endif
 
 #endif /* _UAPI_LINUX_AUXVEC_H */