Comments by "Lawrence D’Oliveiro" (@lawrencedoliveiro9104) on "OS Context Switching - Computerphile" video.

  1. 9:09 You’ve already said that the registers seen by the OS kernel are not the same as those seen in user mode, even though they have the same names. So presumably the OS has access to special instructions for accessing the user-mode registers, in order to do this save/restore (and no doubt other purposes like obtaining arguments and returning results for SWI calls)?
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  2. No, the registers have the same names, but kernel mode has its own separate registers. This avoids having to save/restore registers when switching modes.
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