From f912696ab330bf539231d1f8032320f2a08b850f Mon Sep 17 00:00:00 2001 From: Bart Oldeman <bartoldeman@users.sourceforge.net> Date: Sun, 6 Nov 2005 12:54:07 +1300 Subject: [PATCH] reset tss->io_bitmap_owner in sys_ioperm() my patch "x86: initialise tss->io_bitmap_owner to something" (commit ID d5cd4aadd3d220afac8e3e6d922e333592551f7d) introduced a problem with a program (DOSEMU) that called ioperm after already doing some port i/o. The problem is that a process switch return causes tss->io_bitmap_base to be set to IO_BITMAP_OFFSET so that the fault (that *really* sets the io bitmap) never triggers. This fixes that regression. Signed-off-by: Bart Oldeman <bartoldeman@users.sourceforge.net> Signed-off-by: Linus Torvalds <torvalds@osdl.org> --- arch/i386/kernel/ioport.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'arch') diff --git a/arch/i386/kernel/ioport.c b/arch/i386/kernel/ioport.c index f2b37654777..b59a34dbe26 100644 --- a/arch/i386/kernel/ioport.c +++ b/arch/i386/kernel/ioport.c @@ -108,8 +108,11 @@ asmlinkage long sys_ioperm(unsigned long from, unsigned long num, int turn_on) /* * Sets the lazy trigger so that the next I/O operation will * reload the correct bitmap. + * Reset the owner so that a process switch will not set + * tss->io_bitmap_base to IO_BITMAP_OFFSET. */ tss->io_bitmap_base = INVALID_IO_BITMAP_OFFSET_LAZY; + tss->io_bitmap_owner = NULL; put_cpu(); -- cgit v1.2.3-18-g5258