[AMD Official Use Only - General] Just posted updated patch addressing the comment -----Original Message----- From: Kuehling, Felix <Felix.Kuehling@xxxxxxx> Sent: Monday, June 6, 2022 7:57 PM To: Errabolu, Ramesh <Ramesh.Errabolu@xxxxxxx>; amd-gfx list <amd-gfx@xxxxxxxxxxxxxxxxxxxxx> Subject: Re: [PATCH 2/3] drm/amdgpu: Add peer-to-peer support among PCIe connected AMD GPUs Am 2022-06-04 um 06:23 schrieb Errabolu, Ramesh: >> +bool amdgpu_device_is_peer_accessible(struct amdgpu_device *adev, >> + struct amdgpu_device *peer_adev) { #ifdef >> +CONFIG_HSA_AMD_P2P >> + bool p2p_access = false; >> + uint64_t address_mask = peer_adev->dev->dma_mask ? >> + ~*peer_adev->dev->dma_mask : ~((1ULL << 32) - 1); >> + resource_size_t aper_limit = >> + adev->gmc.aper_base + adev->gmc.aper_size - 1; >> + p2p_access = !(pci_p2pdma_distance_many(adev->pdev, >> +&peer_adev->dev, 1, true) < 0); > This would give you a checkpatch warning. Please run checkpatch. > > Why can't you initialize p2p_access in the declaration above? > > Ramesh: I did run checkpatch script, and it didn't complain about the variable being not initialized. Being a variable of extern class, it is initialized at load time to default value of ZERO. This is then overridden in amdgpu_drv.c to true. So initializing it to true does not accomplish anything. p2p_access is a local variable. Are you talking about pcie_p2p? Checkpatch is not a static analyzer, it would not complain about uninitialized variables. It's more of a coding style checker. It usually complains when there is no blank line between variable declarations and the function body. That's why I suggested initializing p2p_access with its final value where it's defined 3 lines above, and removing the extra assignment that violates the coding style. Ramesh: I was misunderstanding your comment as being for pcie_p2p module parameter Regards, Felix