[U-Boot] mtd partitions go away

[Boris Brezillon]

On Thu, 15 Nov 2018 16:15:51 +0100
Boris Brezillon <boris.brezillon at bootlin.com> wrote:

> Hi Heiko, 
> 
> On Thu, 15 Nov 2018 15:21:31 +0100
> Boris Brezillon <boris.brezillon at bootlin.com> wrote:
> 
> > 
> > Looks like spi_flash_mtd_register() is doing something really bad here
> > [1]: memsetting the global sf_mtd_info object without testing if
> > this object has already been registered, and then registering it again
> > to the MTD layer. So any partition that had been attached to the mtd
> > object through mtd_probe_devices() are lost, and mtdparts/mtdids are not
> > parsed again because they haven't changed since the last time
> > mtd_probe_devices() was called.
> > 
> > [1]https://elixir.bootlin.com/u-boot/v2018.11/source/drivers/mtd/spi/sf_mtd.c#L76  
> 
> Can you try with the following diff applied?

If the previous diff did not fix your problem, you can try this one

--->8---
diff --git a/drivers/mtd/mtd_uboot.c b/drivers/mtd/mtd_uboot.c
index 5ca560c96879..af5ad25cc37a 100644
--- a/drivers/mtd/mtd_uboot.c
+++ b/drivers/mtd/mtd_uboot.c
@@ -164,6 +164,7 @@ int mtd_probe_devices(void)
        /* Check if mtdparts/mtdids changed since last call, otherwise: exit */
        if ((!mtdparts && !old_mtdparts && !mtdids && !old_mtdids) ||
            (mtdparts && old_mtdparts && mtdids && old_mtdids &&
+            !mtd_dev_list_updated() &&
             !strcmp(mtdparts, old_mtdparts) &&
             !strcmp(mtdids, old_mtdids)))
                return 0;
diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c
index fb6c779abbfe..7a15ded8c883 100644
--- a/drivers/mtd/mtdcore.c
+++ b/drivers/mtd/mtdcore.c
@@ -87,14 +87,17 @@ struct idr_layer {
 
 struct idr {
        struct idr_layer id[MAX_IDR_ID];
+       bool updated;
 };
 
 #define DEFINE_IDR(name)       struct idr name;
 
 void idr_remove(struct idr *idp, int id)
 {
-       if (idp->id[id].used)
+       if (idp->id[id].used) {
                idp->id[id].used = 0;
+               idp->updated = true;
+       }
 
        return;
 }
@@ -134,6 +137,7 @@ int idr_alloc(struct idr *idp, void *ptr, int start, int end, gfp_t gfp_mask)
                if (idl->used == 0) {
                        idl->used = 1;
                        idl->ptr = ptr;
+                       idp->updated = true;
                        return i;
                }
                i++;
@@ -155,6 +159,16 @@ struct mtd_info *__mtd_next_device(int i)
 }
 EXPORT_SYMBOL_GPL(__mtd_next_device);
 
+bool mtd_dev_list_updated(void)
+{
+       if (mtd_idr.updated) {
+               mtd_idr.updated = false;
+               return true;
+       }
+
+       return false;
+}
+
 #ifndef __UBOOT__
 static LIST_HEAD(mtd_notifiers);
 
diff --git a/include/linux/mtd/mtd.h b/include/linux/mtd/mtd.h
index 68e591532492..d20ebd820289 100644
--- a/include/linux/mtd/mtd.h
+++ b/include/linux/mtd/mtd.h
@@ -581,6 +581,7 @@ int mtd_arg_off_size(int argc, char *const argv[], int *idx, loff_t *off,
 void mtd_get_len_incl_bad(struct mtd_info *mtd, uint64_t offset,
                          const uint64_t length, uint64_t *len_incl_bad,
                          int *truncated);
+bool mtd_dev_list_updated(void);
 
 /* drivers/mtd/mtd_uboot.c */
 int mtd_search_alternate_name(const char *mtdname, char *altname,