On Mon, 24 Apr 2023 12:38:46 +0100, Lucas Tanure wrote: > Change the scanning /memreserve/ and /reserved-memory node order to fix > Kernel panic on Khadas Vim3 Board. > > If /memreserve/ goes first, the memory is reserved, but nomap can't be > applied to the region. So the memory won't be used by Linux, but it is > still present in the linear map as normal memory, which allows > speculation. Legitimate access to adjacent pages will cause the CPU > to end up prefetching into them leading to Kernel panic. > > So /reserved-memory node should go first, as it has a more updated > description of the memory regions and can apply flags, like nomap. > > Signed-off-by: Lucas Tanure <tanure@xxxxxxxxx>i > --- > Previous Threads: > #regzbot link: https://lore.kernel.org/linux-arm-kernel/40ca11f84b7cdbfb9ad2ddd480cb204a@xxxxxxxx/#regzbot > #regzbot link: https://lore.kernel.org/all/CAJX_Q+1Tjc+-TjZ6JW9X0NxEdFe=82a9626yL63j7uVD4LpxEA@xxxxxxxxxxxxxx/ Note that this should have been a 'Link:' entry in the commit message for regzbot. I added it. > > V1: https://lore.kernel.org/all/20230406151429.524591-1-tanure@xxxxxxxxx/ > v2: https://lore.kernel.org/all/20230410120017.41664-1-tanure@xxxxxxxxx/ > v3: https://lore.kernel.org/linux-mm/20230412224620.8909-1-tanure@xxxxxxxxx/T/ > > Change from V3: > - Drop cover letter > - Add more information into the patch > > Change from V2: > - Remove region overlap and reserved checks > > Change from V1: > - Instead of allowing to mark nomap a region already reserved, give > precedence to /reserved-memory node scan. > --- > drivers/of/fdt.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > Applied, thanks! Going to let this sit in linux-next for a bit. I also didn't tag for stable kernels. I want it to get some exposure in mainline at least for a few -rc releases rather than getting backported right away. Please help ensure that happens if you see stable review emails. I'm going to be offline most of the next month. Rob
