From a5f6096c805e6d2fa03ee932f8c70af34cee41a0 Mon Sep 17 00:00:00 2001 From: Jeff Dike Date: Tue, 16 Oct 2007 01:27:15 -0700 Subject: uml: floating point signal delivery fixes Handle floating point state in across signals correctly. UML/i386 needs to know whether the host does PTRACE_[GS]ETFPXREGS, so an arch_init_registers hook is added, which on x86_64 does nothing. UML doesn't save and restore floating point registers on kernel entry and exit, so they need to be copied between the host process and the sigcontext. save_fpx_registers and restore_fpx_registers are added for this purpose. save_fp_registers and restore_fp_registers already exist. There was a bunch of floating point state conversion code in arch/um/sys-i386/ptrace.c which isn't needed there, but is needed in signal.c, so it is moved over. The i386 code now distinguishes between fp and fpx state and handles them correctly. The x86_64 code just needs to copy state as-is between the host process and the stack. There are also some fixes there to pass the correct address of the floating point state around. Signed-off-by: Jeff Dike Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/um/os-Linux/sys-i386/registers.c | 35 ++++++++++++++++++++++++++++++++--- 1 file changed, 32 insertions(+), 3 deletions(-) (limited to 'arch/um/os-Linux/sys-i386') diff --git a/arch/um/os-Linux/sys-i386/registers.c b/arch/um/os-Linux/sys-i386/registers.c index f171204caa4e..8f1f0ab639b9 100644 --- a/arch/um/os-Linux/sys-i386/registers.c +++ b/arch/um/os-Linux/sys-i386/registers.c @@ -8,9 +8,6 @@ #include "longjmp.h" #include "user.h" -/* XXX These need to use [GS]ETFPXREGS and copy_sc_{to,from}_user_skas needs - * to pass in a sufficiently large buffer - */ int save_fp_registers(int pid, unsigned long *fp_regs) { if(ptrace(PTRACE_GETFPREGS, pid, 0, fp_regs) < 0) @@ -25,6 +22,20 @@ int restore_fp_registers(int pid, unsigned long *fp_regs) return 0; } +int save_fpx_registers(int pid, unsigned long *fp_regs) +{ + if(ptrace(PTRACE_GETFPXREGS, pid, 0, fp_regs) < 0) + return -errno; + return 0; +} + +int restore_fpx_registers(int pid, unsigned long *fp_regs) +{ + if(ptrace(PTRACE_SETFPXREGS, pid, 0, fp_regs) < 0) + return -errno; + return 0; +} + unsigned long get_thread_reg(int reg, jmp_buf *buf) { switch(reg){ @@ -36,3 +47,21 @@ unsigned long get_thread_reg(int reg, jmp_buf *buf) return 0; } } + +int have_fpx_regs = 1; + +void arch_init_registers(int pid) +{ + unsigned long fpx_regs[HOST_XFP_SIZE]; + int err; + + err = ptrace(PTRACE_GETFPXREGS, pid, 0, fpx_regs); + if(!err) + return; + + if(errno != EIO) + panic("check_ptrace : PTRACE_GETFPXREGS failed, errno = %d", + errno); + + have_fpx_regs = 0; +} -- cgit v1.2.3