John reports that the recently merged commit 1a8e1cef76 ("arm64: use
both ZONE_DMA and ZONE_DMA32") breaks the boot on his DB845C board:
| Booting Linux on physical CPU 0x0000000000 [0x517f803c]
| Linux version 5.4.0-mainline-10675-g957a03b9e38f
| Machine model: Thundercomm Dragonboard 845c
| [...]
| Built 1 zonelists, mobility grouping on. Total pages: -188245
| Kernel command line: earlycon
| firmware_class.path=/vendor/firmware/ androidboot.hardware=db845c
| init=/init androidboot.boot_devices=soc/1d84000.ufshc
| printk.devkmsg=on buildvariant=userdebug root=/dev/sda2
| androidboot.bootdevice=1d84000.ufshc androidboot.serialno=c4e1189c
| androidboot.baseband=sda
| msm_drm.dsi_display0=dsi_lt9611_1080_video_display:
| androidboot.slot_suffix=_a skip_initramfs rootwait ro init=/init
|
| <hangs indefinitely here>
This is because, when CONFIG_NUMA=n, zone_sizes_init() fails to handle
memblocks that fall entirely within the ZONE_DMA region and erroneously ends up
trying to add a negatively-sized region into the following ZONE_DMA32, which is
later interpreted as a large unsigned region by the core MM code.
Rework the non-NUMA implementation of zone_sizes_init() so that the start
address of the memblock being processed is adjusted according to the end of the
previous zone, which is then range-checked before updating the hole information
of subsequent zones.
Cc: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/lkml/CALAqxLVVcsmFrDKLRGRq7GewcW405yTOxG=KR3csVzQ6bXutkA@mail.gmail.com
Fixes: 1a8e1cef76 ("arm64: use both ZONE_DMA and ZONE_DMA32")
Reported-by: John Stultz <john.stultz@linaro.org>
Tested-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
93b90414c3