Thomas Gleixner ecc7e37d4d x86/io: Speedup schedule out of I/O bitmap user ... There is no requirement to update the TSS I/O bitmap when a thread using it is scheduled out and the incoming thread does not use it. For the permission check based on the TSS I/O bitmap the CPU calculates the memory location of the I/O bitmap by the address of the TSS and the io_bitmap_base member of the tss_struct. The easiest way to invalidate the I/O bitmap is to switch the offset to an address outside of the TSS limit. If an I/O instruction is issued from user space the TSS limit causes #GP to be raised in the same was as valid I/O bitmap with all bits set to 1 would do. This removes the extra work when an I/O bitmap using task is scheduled out and puts the burden on the rare I/O bitmap users when they are scheduled in. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>		2019-11-16 11:24:01 +01:00
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asm	x86/io: Speedup schedule out of I/O bitmap user	2019-11-16 11:24:01 +01:00
uapi/asm	kvm: svm: Intercept RDPRU	2019-09-24 16:15:36 +02:00