Revert "media: vivid: shut up warnings due to a non-trivial logic"

0day kernel testing robot got the below dmesg and the first bad commit is

https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master
commit 3354b54f9f7037a1122d3b6009aa9d39829d6843

[  248.847809] BUG: unable to handle kernel paging request at ffffc90000393131

[  248.848015] Call Trace:
[  248.848015]  ? vivid_dev_release+0xc0/0xc0
[  248.848015]  ? acpi_dev_pm_attach+0x27/0xd0

This reverts commit 3354b54f9f7037a1122d3b6009aa9d39829d6843.

diff --git a/drivers/media/platform/vivid/vivid-core.c b/drivers/media/platform/vivid/vivid-core.c
index 4c235ea27987581f059f1ff7f05a0e4d053eeb79..31db363602e5313e88d253f1fb77b9b06652efd9 100644 (file)
--- a/drivers/media/platform/vivid/vivid-core.c
+++ b/drivers/media/platform/vivid/vivid-core.c
@@ -647,7 +647,6 @@ static int vivid_create_instance(struct platform_device *pdev, int inst)
        unsigned node_type = node_types[inst];
        unsigned int allocator = allocators[inst];
        v4l2_std_id tvnorms_cap = 0, tvnorms_out = 0;
-       char *strings_base;
        int ret;
        int i;
 
@@ -860,33 +859,17 @@ static int vivid_create_instance(struct platform_device *pdev, int inst)
        /* create a string array containing the names of all the preset timings */
        while (v4l2_dv_timings_presets[dev->query_dv_timings_size].bt.width)
                dev->query_dv_timings_size++;
-
-       /*
-        * In order to save one allocation and an extra free, let's optimize
-        * the allocation here: we'll use the first elements of the
-        * dev->query_dv_timings_qmenu to store the timing strings pointer,
-        * adding an extra space there to a store a string up to 32 bytes.
-        * So, instead of allocating an array with size of:
-        *      dev->query_dv_timings_size * (sizeof(void *)
-        * it will allocate:
-        *      dev->query_dv_timings_size * (sizeof(void *) +
-        *      dev->query_dv_timings_size * 32
-        */
        dev->query_dv_timings_qmenu = kmalloc_array(dev->query_dv_timings_size,
                                                    (sizeof(void *) + 32),
                                                    GFP_KERNEL);
        if (dev->query_dv_timings_qmenu == NULL)
                goto free_dev;
-
-       /* Sets strings_base to be after the space to store the pointers */
-       strings_base = ((char *)&dev->query_dv_timings_qmenu)
-                      + dev->query_dv_timings_size * sizeof(void *);
-
        for (i = 0; i < dev->query_dv_timings_size; i++) {
                const struct v4l2_bt_timings *bt = &v4l2_dv_timings_presets[i].bt;
-               char *p = strings_base + i * 32;
+               char *p = (char *)&dev->query_dv_timings_qmenu[dev->query_dv_timings_size];
                u32 htot, vtot;
 
+               p += i * 32;
                dev->query_dv_timings_qmenu[i] = p;
 
                htot = V4L2_DV_BT_FRAME_WIDTH(bt);