GFP_HIGHUSER is for userspace allocations that may be mapped to userspace,An example may be a hardware allocation that maps data directly into userspace but has no addressing limitations, this conflicts with GFP_DMA32,The kernel reports a BUG: kernel BUG at include/linux/gfp.h:139! Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP Modules linked in: Hardware name: NXP i.MX8MPlus EVK board (DT) pstate: 40000005 (nZcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : __alloc_pages_noprof+0x5d8/0x72c lr : alloc_pages_mpol_noprof+0x100/0x4e0 sp : ffffffc08c6a71c0 x29: ffffffc08c6a71c0 x28: ffffffc086e46000 x27: ffffffc086e46a68 x26: 1ffffff81122b260 x25: ffffffc089159304 x24: ffffff80da938000 x23: 0000000000000000 x22: 0000000000000000 x21: ffffff80da938000 x20: 1ffffff8118d4e46 x19: 0000000000146cc6 x18: 0000000000000000 x17: ffffffc081b00980 x16: ffffffc081b002a8 x15: 1ffffff8118d4e56 x14: 00000000f1f1f1f1 x13: 00000000f3f3f300 x12: 0000000000000000 x11: ffffff80da9384c8 x10: ffffff80da938000 x9 : 00000000f2f2f200 x8 : 0000000041b58ab3 x7 : 00000000f3000000 x6 : 00000000f3f3f3f3 x5 : 1ffffff01b527005 x4 : 000000000000000c x3 : 0000000000000006 x2 : 0000000000000000 x1 : 00000000000003a3 x0 : 0000000000000000 Call trace: __alloc_pages_noprof+0x5d8/0x72c alloc_pages_mpol_noprof+0x100/0x4e0 folio_alloc_mpol_noprof+0x18/0xb8 shmem_alloc_folio+0x154/0x1a8 shmem_alloc_and_add_folio+0x180/0xee8 shmem_get_folio_gfp+0x660/0x103c shmem_read_folio_gfp+0x98/0x104 drm_gem_get_pages+0x174/0x5ac etnaviv_gem_shmem_get_pages+0x18/0x5c etnaviv_gem_get_pages+0x100/0x328 etnaviv_gem_cpu_prep+0x2e8/0x438 etnaviv_ioctl_gem_cpu_prep+0xb0/0x1ac drm_ioctl_kernel+0x158/0x2c8 drm_ioctl+0x494/0xb48 __arm64_sys_ioctl+0x120/0x18c invoke_syscall+0x6c/0x25c el0_svc_common.constprop.0+0x174/0x278 do_el0_svc+0x40/0x58 el0_svc+0x50/0xc0 el0t_64_sync_handler+0xc0/0xc4 el0t_64_sync+0x190/0x194 Code: 52800021 39003c01 d4210000 17ffff57 (d4210000) Fixes: b72af445cd38 ("drm/etnaviv: request pages from DMA32 zone when needed") Signed-off-by: Xiaolei Wang <xiaolei.wang@xxxxxxxxxxxxx> --- drivers/gpu/drm/etnaviv/etnaviv_gpu.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c index 7c7f97793ddd..c3f329226bed 100644 --- a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c +++ b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c @@ -844,8 +844,10 @@ int etnaviv_gpu_init(struct etnaviv_gpu *gpu) * request pages for our SHM backend buffers from the DMA32 zone to * hopefully avoid performance killing SWIOTLB bounce buffering. */ - if (dma_addressing_limited(gpu->dev)) - priv->shm_gfp_mask |= GFP_DMA32; + if (dma_addressing_limited(gpu->dev)) { + priv->shm_gfp_mask |= GFP_DMA32 & GFP_USER; + priv->shm_gfp_mask &= ~GFP_HIGHUSER; + } /* Create buffer: */ ret = etnaviv_cmdbuf_init(priv->cmdbuf_suballoc, &gpu->buffer, -- 2.25.1