diff options
| author | Alexander Usyskin <alexander.usyskin@intel.com> | 2026-07-19 12:57:55 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2026-07-31 13:28:05 +0200 |
| commit | b0495bb58af06a7de4628c72d500e3d5e180d808 (patch) | |
| tree | 8a7326a6c17064bc2cdbf904c23039af89f2e959 | |
| parent | dd7aea9ee2091cfae3a5e376af87aa106d7735cd (diff) | |
mei: pull kvfree out of spinlock
The read buffer allocation was changed from kmalloc() to kvmalloc().
This buffer is part of mei_cl_cb structure that can be queued in
rd_complete queue protected by spinlock.
Releasing the structure leads to errors like below when freeing buffer
that allocated non-contiguous:
BUG: sleeping function called from invalid context at mm/vmalloc.c:3448
Separate mei_cl_cb structure dequeue and release to
perform only dequeue under spinlock and push release out of spinlock.
Cc: stable <stable@kernel.org>
Fixes: 4adf613e01bf ("mei: use kvmalloc for read buffer")
Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/work_items/16359
Reviewed-by: Menachem Adin <menachem.adin@intel.com>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Link: https://patch.msgid.link/20260719-kvfree_out_of_spinlock-v1-1-e07d6333bea7@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/misc/mei/client.c | 25 |
1 files changed, 15 insertions, 10 deletions
diff --git a/drivers/misc/mei/client.c b/drivers/misc/mei/client.c index 643b0039cc72..26d2b2742d50 100644 --- a/drivers/misc/mei/client.c +++ b/drivers/misc/mei/client.c @@ -425,18 +425,24 @@ static void mei_io_tx_list_free_cl(struct list_head *head, } /** - * mei_io_list_free_fp - free cb from a list that matches file pointer + * mei_io_rd_list_free_fp - free cb from a rd_completed list that matches file pointer * - * @head: io list + * @cl: host client * @fp: file pointer (matching cb file object), may be NULL */ -static void mei_io_list_free_fp(struct list_head *head, const struct file *fp) +static void mei_io_rd_list_free_fp(struct mei_cl *cl, const struct file *fp) { struct mei_cl_cb *cb, *next; + LIST_HEAD(cmpl_list); - list_for_each_entry_safe(cb, next, head, list) + spin_lock(&cl->rd_completed_lock); + list_for_each_entry_safe(cb, next, &cl->rd_completed, list) if (!fp || fp == cb->fp) - mei_io_cb_free(cb); + list_move(&cb->list, &cmpl_list); + spin_unlock(&cl->rd_completed_lock); + + list_for_each_entry_safe(cb, next, &cmpl_list, list) + mei_io_cb_free(cb); } /** @@ -565,9 +571,7 @@ int mei_cl_flush_queues(struct mei_cl *cl, const struct file *fp) mei_io_list_flush_cl(&cl->dev->ctrl_rd_list, cl); mei_cl_free_pending(cl); } - spin_lock(&cl->rd_completed_lock); - mei_io_list_free_fp(&cl->rd_completed, fp); - spin_unlock(&cl->rd_completed_lock); + mei_io_rd_list_free_fp(cl, fp); return 0; } @@ -1401,7 +1405,7 @@ void mei_cl_add_rd_completed(struct mei_cl *cl, struct mei_cl_cb *cb) } /** - * mei_cl_del_rd_completed - free read completed callback with lock + * mei_cl_del_rd_completed - unlink read completed callback with lock and free it * * @cl: host client * @cb: callback block @@ -1410,8 +1414,9 @@ void mei_cl_add_rd_completed(struct mei_cl *cl, struct mei_cl_cb *cb) void mei_cl_del_rd_completed(struct mei_cl *cl, struct mei_cl_cb *cb) { spin_lock(&cl->rd_completed_lock); - mei_io_cb_free(cb); + list_del_init(&cb->list); spin_unlock(&cl->rd_completed_lock); + mei_io_cb_free(cb); } /** |