[PATCH] drm/amdgpu: Reduce stack usage in IP block soft reset

[Srinivasan Shanmugam]

amdgpu_device_ip_soft_reset() allocates an array of AMDGPU_MAX_RINGS
ring pointers on the stack. On 64-bit builds this consumes around 1280
bytes and triggers:

warning: stack frame size (1304) exceeds limit (1024)

Move the temporary ring pointer array to heap allocation to reduce stack
usage.

Fixes: a6319ac34a13 ("drm/amdgpu: Add IP block soft reset as a GPU recovery 
method")
Cc: Alex Deucher <alexander.deuc...@amd.com>
Cc: Timur Kristóf <timur.kris...@gmail.com>
Signed-off-by: Srinivasan Shanmugam <srinivasan.shanmu...@amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_ip.c | 19 ++++++++++++++-----
 1 file changed, 14 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ip.c 
b/drivers/gpu/drm/amd/amdgpu/amdgpu_ip.c
index 65505bc50399..eeb9383b1010 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ip.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ip.c
@@ -524,7 +524,7 @@ int amdgpu_device_ip_soft_reset(struct amdgpu_ring 
*guilty_ring,
                                struct amdgpu_fence *guilty_fence)
 {
        struct amdgpu_device *adev = guilty_ring->adev;
-       struct amdgpu_ring *rings[AMDGPU_MAX_RINGS];
+       struct amdgpu_ring **rings;
        struct amdgpu_ip_block *ip_block;
        enum amd_ip_block_type ip_type;
        u32 num_rings, ring_type_mask;
@@ -539,6 +539,10 @@ int amdgpu_device_ip_soft_reset(struct amdgpu_ring 
*guilty_ring,
                return -EOPNOTSUPP;
        }
 
+       rings = kcalloc(AMDGPU_MAX_RINGS, sizeof(*rings), GFP_KERNEL);
+       if (!rings)
+               return -ENOMEM;
+
        dev_err(adev->dev, "Starting %s IP block soft reset\n",
                ip_block->version->funcs->name);
 
@@ -546,20 +550,25 @@ int amdgpu_device_ip_soft_reset(struct amdgpu_ring 
*guilty_ring,
        amdgpu_filter_rings(adev, ring_type_mask, rings, &num_rings);
 
        amdgpu_device_lock_reset_domain(adev->reset_domain);
-       amdgpu_multi_ring_reset_helper_begin(rings, num_rings, guilty_ring, 
guilty_fence);
+       amdgpu_multi_ring_reset_helper_begin(rings, num_rings, guilty_ring,
+                                            guilty_fence);
 
        r = ip_block->version->funcs->soft_reset(ip_block);
 
-       r = amdgpu_multi_ring_reset_helper_end(rings, num_rings, guilty_ring, 
r);
+       r = amdgpu_multi_ring_reset_helper_end(rings, num_rings, guilty_ring,
+                                              r);
        amdgpu_device_unlock_reset_domain(adev->reset_domain);
 
        if (r) {
                dev_err(adev->dev, "Failed %s IP block soft reset: %d\n",
                        ip_block->version->funcs->name, r);
-               return r;
+               goto out_free;
        }
 
        dev_err(adev->dev, "Successful %s IP block soft reset\n",
                ip_block->version->funcs->name);
-       return 0;
+
+out_free:
+       kfree(rings);
+       return r;
 }
-- 
2.34.1