mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2026-05-12 15:08:25 -04:00
dc398a084d
NMI interrupts should exit with EXCEPTION_RESTORE_REGS not with interrupt_return_srr, which is what the perf NMI handler currently does. This breaks if a PMI hits after interrupt_exit_user_prepare_main() has switched the context tracking to user mode, then the CT_WARN_ON() in interrupt_exit_kernel_prepare() fires because it returns to kernel with context set to user. This could possibly be solved by soft-disabling PMIs in the exit path, but that reduces our ability to profile that code. The warning could be removed, but it's potentially useful. All other NMIs and soft-NMIs return using EXCEPTION_RESTORE_REGS, so this makes perf interrupts consistent with that and seems like the best fix. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Squash in fixups from Nick] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20221006140413.126443-3-npiggin@gmail.com
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.