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  • Miroslav Benes's avatar
    livepatch: doc: remove the limitation for schedule() patching · 372e2db7
    Miroslav Benes authored
    The Limitations section of the documentation describes the impossibility
    to livepatch anything that is inlined to __schedule() function. This had
    been true till 4.9 kernel came. Thanks to commit 0100301b
    
    
    ("sched/x86: Rewrite the switch_to() code") from Brian Gerst there is
    __switch_to_asm function now (implemented in assembly) called properly
    from context_switch(). RIP is thus saved on the stack and a task would
    return to proper version of __schedule() et al. functions.
    
    Of course __switch_to_asm() is not patchable for the reason described in
    the section. But there is no __fentry__ call and I cannot imagine a
    reason to do it anyway.
    
    Therefore, remove the paragraphs from the section.
    
    Signed-off-by: default avatarMiroslav Benes <mbenes@suse.cz>
    Reviewed-by: default avatarPetr Mladek <pmladek@suse.com>
    Acked-by: default avatarJosh Poimboeuf <jpoimboe@redhat.com>
    Signed-off-by: default avatarJiri Kosina <jkosina@suse.cz>
    372e2db7