This is a note to let you know that I've just added the patch titled net: encx24j600: Fix invalid logic in reading of MISTAT register to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: net-encx24j600-fix-invalid-logic-in-reading-of-mista.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit d64a87cef5777e797a929d3d69add243990c539c Author: Valentina Goncharenko <goncharenko.vp@xxxxxxxxx> Date: Thu Dec 1 20:34:08 2022 +0300 net: encx24j600: Fix invalid logic in reading of MISTAT register [ Upstream commit 25f427ac7b8d89b0259f86c0c6407b329df742b2 ] A loop for reading MISTAT register continues while regmap_read() fails and (mistat & BUSY), but if regmap_read() fails a value of mistat is undefined. The patch proposes to check for BUSY flag only when regmap_read() succeed. Compile test only. Found by Linux Verification Center (linuxtesting.org) with SVACE. Fixes: d70e53262f5c ("net: Microchip encx24j600 driver") Signed-off-by: Valentina Goncharenko <goncharenko.vp@xxxxxxxxx> Reviewed-by: Pavan Chebbi <pavan.chebbi@xxxxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/net/ethernet/microchip/encx24j600-regmap.c b/drivers/net/ethernet/microchip/encx24j600-regmap.c index 44e656048c51..668a63abe0cb 100644 --- a/drivers/net/ethernet/microchip/encx24j600-regmap.c +++ b/drivers/net/ethernet/microchip/encx24j600-regmap.c @@ -363,7 +363,7 @@ static int regmap_encx24j600_phy_reg_read(void *context, unsigned int reg, goto err_out; usleep_range(26, 100); - while (((ret = regmap_read(ctx->regmap, MISTAT, &mistat)) != 0) && + while (((ret = regmap_read(ctx->regmap, MISTAT, &mistat)) == 0) && (mistat & BUSY)) cpu_relax(); @@ -401,7 +401,7 @@ static int regmap_encx24j600_phy_reg_write(void *context, unsigned int reg, goto err_out; usleep_range(26, 100); - while (((ret = regmap_read(ctx->regmap, MISTAT, &mistat)) != 0) && + while (((ret = regmap_read(ctx->regmap, MISTAT, &mistat)) == 0) && (mistat & BUSY)) cpu_relax();