parisc: Add missing FORCE prerequisites in MakefileFix those make warnings: arch/parisc/kernel/vdso32/Makefile:30: FORCE prerequisite is missing arch/parisc/kernel/vdso64/Makefile:30: FORCE
parisc: Add missing FORCE prerequisites in MakefileFix those make warnings: arch/parisc/kernel/vdso32/Makefile:30: FORCE prerequisite is missing arch/parisc/kernel/vdso64/Makefile:30: FORCE prerequisite is missingAdd the missing FORCE prerequisites for all build targets identified by"make help".Fixes: e1f86d7b4b2a5213 ("kbuild: warn if FORCE is missing for if_changed(_dep,_rule) and filechk")Signed-off-by: Helge Deller <deller@gmx.de>Cc: <stable@vger.kernel.org> # 5.18+
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parisc: Add vDSO supportAdd minimal vDSO support, which provides the signal trampoline helpers,but none of the userspace syscall helpers like time wrappers.The big benefit of this vDSO implement
parisc: Add vDSO supportAdd minimal vDSO support, which provides the signal trampoline helpers,but none of the userspace syscall helpers like time wrappers.The big benefit of this vDSO implementation is, that we now don't needan executeable stack any longer. PA-RISC is one of the lastarchitectures where an executeable stack was needed in oder to implementthe signal trampolines by putting assembly instructions on the stackwhich then gets executed. Instead the kernel will provide the relevantcode in the vDSO page and only put the pointers to the signalinformation on the stack.By dropping the need for executable stacks we avoid running into issueswith applications which want non executable stacks for security reasons.Additionally, alternative stacks on memory areas without execpermissions are supported too.This code is based on an initial implementation by Randolph Chung from 2006:https://lore.kernel.org/linux-parisc/4544A34A.6080700@tausq.org/I did the porting and lifted the code to current code base. Dave fixedthe unwind code so that gdb and glibc are able to backtrace through thecode. An additional patch to gdb will be pushed upstream by Dave.Signed-off-by: Helge Deller <deller@gmx.de>Signed-off-by: Dave Anglin <dave.anglin@bell.net>Cc: Randolph Chung <randolph@tausq.org>Signed-off-by: Helge Deller <deller@gmx.de>