Gaurav Batra 328335a794 powerpc/powernv/iommu: iommu incorrectly bypass DMA APIs ... In a PowerNV environment, for devices that supports DMA mask less than 64 bit but larger than 32 bits, iommu is incorrectly bypassing DMA APIs while allocating and mapping buffers for DMA operations. Devices are failing with ENOMEN during probe with the following messages amdgpu 0000:01:00.0: [drm] Detected VRAM RAM=4096M, BAR=4096M amdgpu 0000:01:00.0: [drm] RAM width 128bits GDDR5 amdgpu 0000:01:00.0: iommu: 64-bit OK but direct DMA is limited by 0 amdgpu 0000:01:00.0: dma_iommu_get_required_mask: returning bypass mask 0xfffffffffffffff amdgpu 0000:01:00.0: 4096M of VRAM memory ready amdgpu 0000:01:00.0: 32570M of GTT memory ready. amdgpu 0000:01:00.0: (-12) failed to allocate kernel bo amdgpu 0000:01:00.0: [drm] Debug VRAM access will use slowpath MM access amdgpu 0000:01:00.0: [drm] GART: num cpu pages 4096, num gpu pages 65536 amdgpu 0000:01:00.0: [drm] PCIE GART of 256M enabled (table at 0x000000F4FFF80000). amdgpu 0000:01:00.0: (-12) failed to allocate kernel bo amdgpu 0000:01:00.0: (-12) create WB bo failed amdgpu 0000:01:00.0: amdgpu_device_wb_init failed -12 amdgpu 0000:01:00.0: amdgpu_device_ip_init failed amdgpu 0000:01:00.0: Fatal error during GPU init amdgpu 0000:01:00.0: finishing device. amdgpu 0000:01:00.0: probe with driver amdgpu failed with error -12 amdgpu 0000:01:00.0: ttm finalized Fixes: 1471c517cf ("powerpc/iommu: bypass DMA APIs for coherent allocations for pre-mapped memory") Suggested-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Reported-by: Dan Horák <dan@danny.cz> Closes: https://gitlab.freedesktop.org/drm/amd/-/work_items/5039 Tested-by: Dan Horak <dan@danny.cz> Closes: https://lore.kernel.org/linuxppc-dev/20260313142351.609bc4c3efe1184f64ca5f44@danny.cz/ Signed-off-by: Gaurav Batra <gbatra@linux.ibm.com> Closes: https://lore.kernel.org/linuxppc-dev/20260313142351.609bc4c3efe1184f64ca5f44@danny.cz/ [Maddy: Fixed tags] Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com> Link: https://patch.msgid.link/20260331223022.47488-1-gbatra@linux.ibm.com		2026-04-01 22:08:55 +05:30
..
boot	powerpc: dts: mpc83xx: Add unit addresses to /memory	2026-03-07 16:02:27 +05:30
configs	mm.git review status for linus..mm-nonmm-stable	2026-02-12 12:13:01 -08:00
crypto	lib/crypto: powerpc/aes: Migrate POWER8 optimized code into library	2026-01-12 11:39:58 -08:00
include	powerpc: fix KUAP warning in VMX usercopy path	2026-03-12 11:03:47 +05:30
kernel	powerpc/powernv/iommu: iommu incorrectly bypass DMA APIs	2026-04-01 22:08:55 +05:30
kexec	powerpc/crash: adjust the elfcorehdr size	2026-03-04 11:12:48 +05:30
kvm	KVM: PPC: e500: Rip out "struct tlbe_ref"	2026-03-11 18:41:10 +01:00
lib	powerpc: fix KUAP warning in VMX usercopy path	2026-03-12 11:03:47 +05:30
math-emu
mm	powerpc/mem: Move CMA reservations to arch_mm_preinit	2026-03-12 10:57:31 +05:30
net	powerpc64/bpf: fix kfunc call support	2026-03-07 16:02:26 +05:30
perf	powerpc, perf: Check that current->mm is alive before getting user callchain	2026-03-12 11:02:55 +05:30
platforms	powerpc/pseries: Correct MSI allocation tracking	2026-03-07 16:02:28 +05:30
purgatory	Makefile: remove redundant tool coverage variables	2024-05-14 23:35:48 +09:00
sysdev	Convert more 'alloc_obj' cases to default GFP_KERNEL arguments	2026-02-21 20:03:00 -08:00
tools	powerpc64/ftrace: fix OOL stub count with clang	2026-03-07 16:02:25 +05:30
xmon	powerpc/xmon: replace sizeof calculations with ARRAY_SIZE macro	2025-09-01 13:40:46 +05:30
Kbuild	powerpc64/ftrace: Move ftrace sequence out of line	2024-10-31 11:00:54 +11:00
Kconfig	powerpc64: make clang cross-build friendly	2026-03-07 16:02:25 +05:30
Kconfig.debug	powerpc: Remove UDBG_RTAS_CONSOLE	2025-02-26 21:15:09 +05:30
Makefile	kbuild: Add missing $(objtree) prefix to powerpc crtsavres.o artifact	2025-09-01 13:41:57 +05:30
Makefile.postlink	powerpc/ftrace: Add a postlink script to validate function tracer	2024-10-31 11:00:54 +11:00