Use kmap_local_page() instead of sg_virt() to obtain a page from the scatterlist: sg_virt() will not perform bounce buffering if the page happens to be located in high memory, which the driver may or may not be using. Suggested-by: Christoph Hellwig <hch@xxxxxx> Link: https://lore.kernel.org/linux-mmc/20240122073423.GA25859@xxxxxx/ Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxx> --- drivers/mmc/host/omap.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/mmc/host/omap.c b/drivers/mmc/host/omap.c index 9fb8995b43a1..3e36480b22ad 100644 --- a/drivers/mmc/host/omap.c +++ b/drivers/mmc/host/omap.c @@ -659,7 +659,7 @@ mmc_omap_sg_to_buf(struct mmc_omap_host *host) sg = host->data->sg + host->sg_idx; host->buffer_bytes_left = sg->length; - host->buffer = sg_virt(sg); + host->buffer = kmap_local_page(sg_page(sg)); if (host->buffer_bytes_left > host->total_bytes_left) host->buffer_bytes_left = host->total_bytes_left; } @@ -691,6 +691,11 @@ mmc_omap_xfer_data(struct mmc_omap_host *host, int write) nwords = DIV_ROUND_UP(n, 2); host->buffer_bytes_left -= n; + if (host->buffer_bytes_left == 0) { + kunmap_local(host->buffer); + host->buffer = NULL; + } + host->total_bytes_left -= n; host->data->bytes_xfered += n; -- 2.34.1