diff --git a/firmware/common/disk.c b/firmware/common/disk.c
index 958f09755a..f016a7c196 100644
--- a/firmware/common/disk.c
+++ b/firmware/common/disk.c
@@ -173,7 +173,7 @@ bool disk_init(IF_MD_NONVOID(int drive))
     disk_writer_unlock();
 
 #ifdef MAX_LOG_SECTOR_SIZE
-    if (info->sector_size > MAX_LOG_SECTOR_SIZE) {
+    if (info->sector_size > MAX_LOG_SECTOR_SIZE || info->sector_size > DC_CACHE_BUFSIZE) {
         panicf("Unsupported logical sector size: %d",
                info->sector_size);
     }
@@ -185,7 +185,7 @@ bool disk_init(IF_MD_NONVOID(int drive))
 #endif
 #endif /* CONFIG_STORAGE & STORAGE_ATA */
 
-    memset(sector, 0, LOG_SECTOR_SIZE(drive));
+    memset(sector, 0, DC_CACHE_BUFSIZE);
     storage_read_sectors(IF_MD(drive,) 0, 1, sector);
 
     bool init = false;
diff --git a/firmware/include/fs_defines.h b/firmware/include/fs_defines.h
index f4c8385d8a..1c8c3afe2b 100644
--- a/firmware/include/fs_defines.h
+++ b/firmware/include/fs_defines.h
@@ -35,14 +35,6 @@
 
 #define MAX_COMPNAME    260
 
-/* still experimental? */
-/* increasing this will increase the total memory used by the cache; the
-   cache, as noted in disk_cache.h, has other minimum requirements that may
-   prevent reducing its number of entries in order to compensate */
-#ifndef SECTOR_SIZE
-#define SECTOR_SIZE     512
-#endif
-
 /* limits for number of open descriptors - if you increase these values, make
    certain that the disk cache has enough available buffers */
 
@@ -108,7 +100,18 @@
 #define DC_MAP_NUM_ENTRIES  256
 #endif /* MEMORYSIZE */
 
+/* increasing this will increase the total memory used by the cache; the
+   cache, as noted in disk_cache.h, has other minimum requirements that may
+   prevent reducing its number of entries in order to compensate */
+#ifndef SECTOR_SIZE
+#define SECTOR_SIZE     512
+#endif
+
 /* this _could_ be larger than a sector if that would ever be useful */
+#ifdef MAX_LOG_SECTOR_SIZE
+#define DC_CACHE_BUFSIZE   MAX_LOG_SECTOR_SIZE
+#else
 #define DC_CACHE_BUFSIZE    SECTOR_SIZE
+#endif
 
 #endif /* FS_DEFINES_H */