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    x86-64: Fix CFI data for interrupt frames · eab9e613
    Jan Beulich authored
    
    
    The patch titled "x86: Don't use frame pointer to save old stack
    on irq entry" did not properly adjust CFI directives, so this
    patch is a follow-up to that one.
    
    With the old stack pointer no longer stored in a callee-saved
    register (plus some offset), we now have to use a CFA expression
    to describe the memory location where it is being found. This
    requires the use of .cfi_escape (allowing arbitrary byte streams
    to be emitted into .eh_frame), as there is no
    .cfi_def_cfa_expression (which also cannot reasonably be
    expected, as it would require a full expression parser).
    
    Signed-off-by: default avatarJan Beulich <jbeulich@suse.com>
    Cc: Frederic Weisbecker <fweisbec@gmail.com>
    Link: http://lkml.kernel.org/r/4E8360200200007800058467@nat28.tlf.novell.com
    
    
    Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
    eab9e613