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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?VRyhx79eMEQIN78tM/FbFmTX9XG/DAdj5R3rzZTW5eMk+EYRypkDdWTXUzbM?= =?us-ascii?Q?tNB5K+3XlkCiaYqX9/GkdxeF6oZFR+4cIcDLrfQUUTlAUkg909vxccTZd/l9?= =?us-ascii?Q?+IMGAz/86ccruIBSRD/J191Di83NHUoyVScJuDNHJGFI5k8/9d8TOXbPzsXc?= =?us-ascii?Q?F7G73/MWQjyS3/5Utm5+b3J6V1upI/vztjoEvRhzUQZJ/IQjZ2WG3P2YLTyv?= =?us-ascii?Q?tiKznnq4i4UjnOQ30eTg1h0Sna+iZFYN4yVUXFyIPSqGT2bB212S8CgJFnM8?= =?us-ascii?Q?0VX3nNwAkwLePvLr/Ey2SCmYVGtReFMV7+cauiw46n0jyKg/I4TSld/d8gRN?= =?us-ascii?Q?F0Gya/j/hW2qa3aPXM5swqJekVfww0xaog2e+/3B4s90so8YRuYDa1BkgevN?= =?us-ascii?Q?xQ/TZNNmMwzvmYk6oHNhaG/j7loSyFK33mNQbVgVm6xhHlNqmuP7iOZqdpC4?= =?us-ascii?Q?cAyjj74ADDPVZT/sFT7ca02laM0i4g4OnfchpIF9EodRk1SPJ/gzZ/GbN8Dt?= =?us-ascii?Q?gkPHOZ5kGQ9KIAHLk+6vKP5gd4UehEoKnqIHoWk0kEPwZqu7zWUK5VECpNQk?= =?us-ascii?Q?N8e5EY72N3j8yV7XHio8zzRZ+Tk0ZHbh1aqSXPXWUEDVyZIJjhNpamYJwIlE?= =?us-ascii?Q?JQnpmN3WOAc2AqZ6N9vnkTcBmU99oCpXaJ+fbG5s9Bq8jh64u7PvaMHQU9Kg?= =?us-ascii?Q?w3DoQ9ypwQ+OV0COfQuFbPo48wJFCSjgmrGM+A6hiEiM/w2lFSA46VmCh0mS?= =?us-ascii?Q?KwArW6D2nxybsz5qvwkifbOAPD+KcswjAdMF/m4Is1h9ERvL4V09wBbRFeSg?= =?us-ascii?Q?U7cRZICr2DFqFcB0sO1EcUzW9GX8KuYhsMwOlU2YUzB5u4VZ3b9E1/pWV9BT?= =?us-ascii?Q?36F+vq+5MbnI1IHsE5kDXYCtkyNKxWjRe8WZLKpBWElWBJsMNkcWY5np7GHz?= =?us-ascii?Q?4gU3tjHYhADj0UZKKIVBjs/j2QY281n8QmQ5v9wDlAqPyT5MD95IQTSQQoF5?= =?us-ascii?Q?xMpLln7gCc6hJ5EfHgAnWj5hCeFanLW4zVm3QSTLQateRn6eeyBCwvnPCi0E?= =?us-ascii?Q?Sd4AlYiGvwNwK28xz/49go7beJ0+w6TPEbWVM+0VS0G0X+KOkXCC0/RFxvDc?= =?us-ascii?Q?2NPpk7yF+dnu554p/nJAKV2OXl1sFh/msBSFVJ7SnYBP1mo3vclARN5NDVxL?= =?us-ascii?Q?ELp8oFu8zpSlcdUJCxlC3t1qlU5+uOG4bc+XJSaNlI3GCuJLCzMw2noGD1nu?= =?us-ascii?Q?8xLjP4V7IEBbY5CgDz0kKDBwMCjsErD3nNIx7Y+WgFufcBkJLB/63zsMDk2W?= =?us-ascii?Q?oKo9hF3JNu0ngJR/M132Sug0vum9nGxyQI8Htmc0fSIs/KbaghsoVvLwdPOI?= =?us-ascii?Q?hhE08mAvK2OTuGagQeHpspQ0DUMxWVFVjByEdJ0dwAVLrBqUFBa6cQ/9xSy9?= =?us-ascii?Q?XjtCjnuWUuoJJK9HEQyw2mcz6yM0FBM2AZCnM5NP9wxCkunG1Uxe0Jenb4jq?= =?us-ascii?Q?OHPZkYiwj9kE+CjYvHAPG5z3W336OSMGyUDJP/6Dvka4mzfxu7b4yXuE/tBJ?= =?us-ascii?Q?wEjpfGWhyV498Q9eUjgOQoRn/oySP+B2JHKyNNT9BMYUhvvrTW6ZMoVJ1nv0?= =?us-ascii?Q?ZdQdzOOKG9YBXy1whlPKCbHsNB95r1qar5GKjVrhPl4nMV53KBtbzN5ZkFAA?= =?us-ascii?Q?VPC2d9QXRexJegJzqEKQyJED3ecJYDV7eD70dywCT+vmqvYo?= X-OriginatorOrg: nxp.com X-MS-Exchange-CrossTenant-Network-Message-Id: e1d58f8d-d746-4803-4d33-08deb0661947 X-MS-Exchange-CrossTenant-AuthSource: PA4PR04MB9366.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 12 May 2026 20:36:09.6061 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 686ea1d3-bc2b-4c6f-a92c-d99c5c301635 X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: 01ULW3Xr5f+8JRFUHLzx/+TdyQzuy19JcV9IajjYpQmFDejNYRCkaGw/0Uvw64fAaSLDqI1qCusW8TPk8+vzGw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: PA1PR04MB10142 On Tue, May 12, 2026 at 03:12:03PM +0300, Claudiu Beznea wrote: > The list passed as argument to list_first_entry() is expected to be not > empty. Little confused, #define list_first_entry_or_null(ptr, type, member) ({ \ struct list_head *head__ = (ptr); \ struct list_head *pos__ = READ_ONCE(head__->next); \ pos__ != head__ ? list_entry(pos__, type, member) : NULL; \ }) both list passed to list_first_entry() or list_first_entry_or_null() must be not NULL. The return value is difference. Fix incorrect NULL check for list_first_entry() list_first_entry() does not return NULL when the list is empty, making the existing NULL check invalid. Use list_first_entry_or_null() instead. Frank > Use list_first_entry_or_null() to avoid dereferencing invalid > memory. > > Fixes: 21323b118c16 ("dmaengine: sh: rz-dmac: Add device_tx_status() callback") > Cc: stable@vger.kernel.org > Signed-off-by: Claudiu Beznea > --- > > Changes in v5: > - none > > Changes in v4: > - none, this patch is new > > drivers/dma/sh/rz-dmac.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/dma/sh/rz-dmac.c b/drivers/dma/sh/rz-dmac.c > index 9f206a33dcc6..6d80cb668957 100644 > --- a/drivers/dma/sh/rz-dmac.c > +++ b/drivers/dma/sh/rz-dmac.c > @@ -723,8 +723,8 @@ static u32 rz_dmac_chan_get_residue(struct rz_dmac_chan *channel, > u32 crla, crtb, i; > > /* Get current processing virtual descriptor */ > - current_desc = list_first_entry(&channel->ld_active, > - struct rz_dmac_desc, node); > + current_desc = list_first_entry_or_null(&channel->ld_active, > + struct rz_dmac_desc, node); > if (!current_desc) > return 0; > > -- > 2.43.0 >