48e08d0fb2
This causes all non-NMI, non-double-fault kernel entries from userspace to run on the normal kernel stack. Double-fault is exempt to minimize confusion if we double-fault directly from userspace due to a bad kernel stack. This is, suprisingly, simpler and shorter than the current code. It removes the IMO rather frightening paranoid_userspace path, and it make sync_regs much simpler. There is no risk of stack overflow due to this change -- the kernel stack that we switch to is empty. This will also enable us to create non-atomic sections within machine checks from userspace, which will simplify memory failure handling. It will also allow the upcoming fsgsbase code to be simplified, because it doesn't need to worry about usergs when scheduling in paranoid_exit, as that code no longer exists. Cc: Oleg Nesterov <oleg@redhat.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Tony Luck <tony.luck@intel.com> Acked-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Andy Lutomirski <luto@amacapital.net> |
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| .. | ||
| i386 | ||
| x86_64 | ||
| 00-INDEX | ||
| boot.txt | ||
| early-microcode.txt | ||
| earlyprintk.txt | ||
| entry_64.txt | ||
| exception-tables.txt | ||
| intel_mpx.txt | ||
| mtrr.txt | ||
| pat.txt | ||
| tlb.txt | ||
| usb-legacy-support.txt | ||
| zero-page.txt | ||