On Fri, Jun 07, 2019 at 03:32:15PM -0400, Josh Poimboeuf wrote: > On Wed, Jun 05, 2019 at 03:07:58PM +0200, Peter Zijlstra wrote: > > Currently pt_regs on x86_32 has an oddity in that kernel regs > > (!user_mode(regs)) are short two entries (esp/ss). This means that any > > code trying to use them (typically: regs->sp) needs to jump through > > some unfortunate hoops. > > > > Change the entry code to fix this up and create a full pt_regs frame. > > > > This then simplifies various trampolines in ftrace and kprobes, the > > stack unwinder, ptrace, kdump and kgdb. > > > > Signed-off-by: Peter Zijlstra (Intel) <pet...@infradead.org> > > > > --- > > arch/x86/entry/entry_32.S | 105 > > ++++++++++++++++++++++++++++++++++---- > > arch/x86/include/asm/kexec.h | 17 ------ > > arch/x86/include/asm/ptrace.h | 17 ------ > > arch/x86/include/asm/stacktrace.h | 2 > > arch/x86/kernel/crash.c | 8 -- > > arch/x86/kernel/ftrace_32.S | 77 +++++++++++++++------------ > > arch/x86/kernel/kgdb.c | 8 -- > > arch/x86/kernel/kprobes/common.h | 4 - > > arch/x86/kernel/kprobes/core.c | 29 ++++------ > > arch/x86/kernel/kprobes/opt.c | 20 ++++--- > > arch/x86/kernel/process_32.c | 16 +---- > > arch/x86/kernel/ptrace.c | 29 ---------- > > arch/x86/kernel/time.c | 3 - > > arch/x86/kernel/unwind_frame.c | 32 +---------- > > arch/x86/kernel/unwind_orc.c | 2 > > 15 files changed, 178 insertions(+), 191 deletions(-) > > I recall writing some of this code (some of the kernel_stack_pointer > removal stuff) so please give me a shout-out ;-)
Absolutely, sorry for not doing that. I've added: "Much thanks to Josh for help with the cleanups!"
