[PATCH] drm/amdgpu: avoid ras error injection for retired page

[Chen, Guchun]

Regards,
Guchun

-----Original Message-----
From: Zhou1, Tao <Tao.Zhou1 at amd.com> 
Sent: Monday, September 30, 2019 2:58 PM
To: amd-gfx at lists.freedesktop.org; Chen, Guchun <Guchun.Chen at amd.com>; Zhang, Hawking <Hawking.Zhang at amd.com>
Cc: Zhou1, Tao <Tao.Zhou1 at amd.com>
Subject: [PATCH] drm/amdgpu: avoid ras error injection for retired page

check whether a page is bad page before error injection

Signed-off-by: Tao Zhou <tao.zhou1 at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c | 38 +++++++++++++++++++++++++
 1 file changed, 38 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c
index fe3a57e567c8..d50e565b0b20 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c
@@ -71,6 +71,9 @@ const char *ras_block_string[] = {
 
 atomic_t amdgpu_ras_in_intr = ATOMIC_INIT(0);
 
+static bool amdgpu_ras_check_bad_page(struct amdgpu_device *adev,
+				uint64_t addr);
+
 static ssize_t amdgpu_ras_debugfs_read(struct file *f, char __user *buf,
 					size_t size, loff_t *pos)
 {
@@ -290,6 +293,13 @@ static ssize_t amdgpu_ras_debugfs_ctrl_write(struct file *f, const char __user *
 			break;
 		}
 
+		/* ce/ue error injection for a bad page is not allowed */
+		if (amdgpu_ras_check_bad_page(adev, data.inject.address)) {
+			DRM_WARN("DRM WARN: 0x%llx has been marked as bad before error injection!\n",
+					data.inject.address);
+			break;
+		}
+
 		/* data.inject.address is offset instead of absolute gpu address */
 		ret = amdgpu_ras_error_inject(adev, &data.inject);
 		break;
@@ -1430,6 +1440,34 @@ static int amdgpu_ras_load_bad_pages(struct amdgpu_device *adev)
 	return ret;
 }
 
+/* check if an address belongs to bad page */ static bool 
+amdgpu_ras_check_bad_page(struct amdgpu_device *adev,
+				uint64_t addr)
+{
+	struct amdgpu_ras *con = amdgpu_ras_get_context(adev);
+	struct ras_err_handler_data *data;
+	int i, ret = false;
[Guchun]It's better to use bool type for the ret variable, to keep consistent with function return type?
Apart from that, this patch is: Reviewed-by: Guchun Chen <guchun.chen at amd.com>

+
+	if (!con || !con->eh_data)
+		return ret;
+
+	mutex_lock(&con->recovery_lock);
+	data = con->eh_data;
+	if (!data)
+		goto out;
+
+	addr >>= AMDGPU_GPU_PAGE_SHIFT;
+	for (i = 0; i < data->count; i++)
+		if (addr == data->bps[i].retired_page) {
+			ret = true;
+			goto out;
+		}
+
+out:
+	mutex_unlock(&con->recovery_lock);
+	return ret;
+}
+
 static void amdgpu_ras_create_bad_pages_bo(struct amdgpu_device *adev)  {
 	/* Note: the caller should guarantee con and data are not NULL */
--
2.17.1