From 5efd63c93c4546978c6a3a8e83c61011721b73b6 Mon Sep 17 00:00:00 2001 From: Nam Cao Date: Thu, 7 Nov 2024 16:01:05 +0100 Subject: [PATCH 1/2] boot: extlinux: Fix unaligned buffer for reading data from file system MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit extlinux_read_bootflow() allocates a buffer to read from file system without any alignment. But for some block devices which transfer data via DMA, ARCH_DMA_MINALIGN alignment is required. For example, due to misaligned buffer, the below boot failure is observed. => boot CACHE: Misaligned operation at range [9efa25f8, 9efa27f8] CACHE: Misaligned operation at range [9efa25f8, 9efa27f8] CACHE: Misaligned operation at range [9efa25f8, 9efa27f8] CACHE: Misaligned operation at range [9efa25f8, 9efa27f8] ** Booting bootflow 'mmc@2194000.bootdev.part_1' with extlinux Ignoring unknown command: �D���D�� Boot failed (err=-14) Change the buffer alignment to ARCH_DMA_MINALIGN. Fixes: 31aefaf89a5b ("bootstd: Add an implementation of distro boot") Signed-off-by: Nam Cao Tested-by: Javier Fernandez Pastrana --- boot/bootmeth_extlinux.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/boot/bootmeth_extlinux.c b/boot/bootmeth_extlinux.c index be8fbf4df63..c6ae6dffcb7 100644 --- a/boot/bootmeth_extlinux.c +++ b/boot/bootmeth_extlinux.c @@ -8,6 +8,7 @@ #define LOG_CATEGORY UCLASS_BOOTSTD +#include #include #include #include @@ -159,7 +160,7 @@ static int extlinux_read_bootflow(struct udevice *dev, struct bootflow *bflow) return log_msg_ret("try", ret); size = bflow->size; - ret = bootmeth_alloc_file(bflow, 0x10000, 1); + ret = bootmeth_alloc_file(bflow, 0x10000, ARCH_DMA_MINALIGN); if (ret) return log_msg_ret("read", ret); From 6ea8dc661b04ddd5c19163932ee12705c53f552a Mon Sep 17 00:00:00 2001 From: Nam Cao Date: Thu, 7 Nov 2024 16:01:06 +0100 Subject: [PATCH 2/2] fs: Use ARCH_DMA_MINALIGN as default alignment for fs_read_alloc() The comment above fs_read_alloc() explains: @align: Alignment to use for memory allocation (0 for default) However, in the actual implementation, there is no alignment when @align is zero. This current default is probably fine for most cases. But for some block devices which transfer data via DMA, ARCH_DMA_MINALIGN is needed. Change the default alignment to ARCH_DMA_MINALIGN. Fixes: de7b5a8a1ac0 ("fs: Create functions to load and allocate a file") Signed-off-by: Nam Cao Tested-by: Javier Fernandez Pastrana --- fs/fs.c | 4 ++++ include/fs.h | 2 +- 2 files changed, 5 insertions(+), 1 deletion(-) diff --git a/fs/fs.c b/fs/fs.c index 1afa0fbeaed..21a23efd932 100644 --- a/fs/fs.c +++ b/fs/fs.c @@ -23,6 +23,7 @@ #include #include #include +#include #include #include #include @@ -1001,6 +1002,9 @@ int fs_read_alloc(const char *fname, ulong size, uint align, void **bufp) char *buf; int ret; + if (!align) + align = ARCH_DMA_MINALIGN; + buf = memalign(align, size + 1); if (!buf) return log_msg_ret("buf", -ENOMEM); diff --git a/include/fs.h b/include/fs.h index 63727567ccc..2474880385d 100644 --- a/include/fs.h +++ b/include/fs.h @@ -325,7 +325,7 @@ int do_fs_types(struct cmd_tbl *cmdtp, int flag, int argc, char * const argv[]); * * @fname: Filename to read * @size: Size of file to read (must be correct!) - * @align: Alignment to use for memory allocation (0 for default) + * @align: Alignment to use for memory allocation (0 for default: ARCH_DMA_MINALIGN) * @bufp: On success, returns the allocated buffer with the nul-terminated file * in it * Return: 0 if OK, -ENOMEM if out of memory, -EIO if read failed