From: Geert Uytterhoeven geert+renesas@glider.be
stable inclusion from stable-5.10.67 commit be2e11b9f8fab49da85a3d79a34f4436c60510df bugzilla: 182619 https://gitee.com/openeuler/kernel/issues/I4EWO7
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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[ Upstream commit 47956bc86ee4e8530cac386a04f62a6095f7afbe ]
As nwl_dsi.lanes is u32, and NSEC_PER_SEC is 1000000000L, the second multiplication in
dsi->lanes * 8 * NSEC_PER_SEC
will overflow on a 32-bit platform. Fix this by making the constant unsigned long long, forcing 64-bit arithmetic.
As iMX8 is arm64, this driver is currently used on 64-bit platforms only, where long is 64-bit, so this cannot happen. But the issue will start to happen when the driver is reused for a 32-bit SoC (e.g. i.MX7ULP), or when code is copied for a new driver.
Signed-off-by: Geert Uytterhoeven geert+renesas@glider.be Reviewed-by: Fabio Estevam festevam@gmail.com Reviewed-by: Laurent Pinchart laurent.pinchart@ideasonboard.com Signed-off-by: Sam Ravnborg sam@ravnborg.org Link: https://patchwork.freedesktop.org/patch/msgid/ebb82941a86b4e35c4fcfb1ef5a5cf... Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Chen Jun chenjun102@huawei.com Acked-by: Weilong Chen chenweilong@huawei.com
Signed-off-by: Chen Jun chenjun102@huawei.com --- drivers/gpu/drm/bridge/nwl-dsi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/bridge/nwl-dsi.c b/drivers/gpu/drm/bridge/nwl-dsi.c index c65ca860712d..6cac2e58cd15 100644 --- a/drivers/gpu/drm/bridge/nwl-dsi.c +++ b/drivers/gpu/drm/bridge/nwl-dsi.c @@ -196,7 +196,7 @@ static u32 ps2bc(struct nwl_dsi *dsi, unsigned long long ps) u32 bpp = mipi_dsi_pixel_format_to_bpp(dsi->format);
return DIV64_U64_ROUND_UP(ps * dsi->mode.clock * bpp, - dsi->lanes * 8 * NSEC_PER_SEC); + dsi->lanes * 8ULL * NSEC_PER_SEC); }
/*