kernel/linux.git/arch/um/include/shared/registers.h, branch linux-5.3.y

um: add extended processor state save/restore support

2016-05-21T21:38:06+00:00

This patch extends save_fp_registers() and restore_fp_registers() to use PTRACE_GETREGSET and PTRACE_SETREGSET with the XSTATE note type, adding support for new processor state extensions between context switches. When the new ptrace requests are unavailable, it falls back to the old PTRACE_GETFPREGS and PTRACE_SETFPREGS methods, which have been renamed to save_i387_registers() and restore_i387_registers(). Now these functions expect *fp_regs to have the space of an _xstate struct. Thus, this also makes ptrace in UML responde to PTRACE_GETFPREGS/_SETFPREG requests with a user_i387_struct (thus independent from HOST_FP_SIZE), and by calling save_i387_registers() and restore_i387_registers() instead of the extended save_fp_registers() and restore_fp_registers() functions. Signed-off-by: Eli Cooper

um: get rid of pointless include "..." where include <...> will do

2012-10-09T20:28:45+00:00

Signed-off-by: Al Viro Signed-off-by: Richard Weinberger

um: Save FPU registers between task switches

2011-09-15T01:09:37+00:00

Some time ago Jeff prepared 42daba316557 ("uml: stop saving process FP state") for UML to stop saving the process FP state between task switches. The assumption was that since with SKAS0 every guest process runs inside a host process context the host OS will take care of keeping the proper FP state. Unfortunately this is not true for multi-threaded applications, where all guest threads share a single host process context yet all may use the FPU on their own. Although I haven't verified it I suspect things to be even worse in SKAS3 mode where all guest processes run inside a single host process. The patch reintroduces the saving and restoring of the FP context between task switches. [richard@nod.at: Ingo posted this patch in 2009, sadly it was never applied and got lost. Now in 2011 the problem was reported by Gunnar.] Signed-off-by: Ingo van Lil Signed-off-by: Richard Weinberger Reported-by: Tested-by: Cc: Stanislav Meduna Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

x86, um: take arch/um/include/* out of the way

2008-10-23T05:55:19+00:00

We can't just plop asm/* into it - userland helpers are built with it in search path and seeing asm/* show up there suddenly would be a bad idea. Signed-off-by: Al Viro Signed-off-by: H. Peter Anvin