From e333eed63a091a09bd0db191b7710c594c6e995b Mon Sep 17 00:00:00 2001 From: Fabio Estevam Date: Wed, 4 May 2022 11:31:03 -0300 Subject: net: phy: micrel: Do not use kszphy_suspend/resume for KSZ8061 Since commit f1131b9c23fb ("net: phy: micrel: use kszphy_suspend()/kszphy_resume for irq aware devices") the following NULL pointer dereference is observed on a board with KSZ8061: # udhcpc -i eth0 udhcpc: started, v1.35.0 8<--- cut here --- Unable to handle kernel NULL pointer dereference at virtual address 00000008 pgd = f73cef4e [00000008] *pgd=00000000 Internal error: Oops: 5 [#1] SMP ARM Modules linked in: CPU: 0 PID: 196 Comm: ifconfig Not tainted 5.15.37-dirty #94 Hardware name: Freescale i.MX6 SoloX (Device Tree) PC is at kszphy_config_reset+0x10/0x114 LR is at kszphy_resume+0x24/0x64 ... The KSZ8061 phy_driver structure does not have the .probe/..driver_data fields, which means that priv is not allocated. This causes the NULL pointer dereference inside kszphy_config_reset(). Fix the problem by using the generic suspend/resume functions as before. Another alternative would be to provide the .probe and .driver_data information into the structure, but to be on the safe side, let's just restore Ethernet functionality by using the generic suspend/resume. Cc: stable@vger.kernel.org Fixes: f1131b9c23fb ("net: phy: micrel: use kszphy_suspend()/kszphy_resume for irq aware devices") Signed-off-by: Fabio Estevam Reviewed-by: Andrew Lunn Link: https://lore.kernel.org/r/20220504143104.1286960-1-festevam@gmail.com Signed-off-by: Jakub Kicinski --- drivers/net/phy/micrel.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers/net/phy') diff --git a/drivers/net/phy/micrel.c b/drivers/net/phy/micrel.c index fc53b71dc872..7c243cedde9f 100644 --- a/drivers/net/phy/micrel.c +++ b/drivers/net/phy/micrel.c @@ -2782,8 +2782,8 @@ static struct phy_driver ksphy_driver[] = { .config_init = ksz8061_config_init, .config_intr = kszphy_config_intr, .handle_interrupt = kszphy_handle_interrupt, - .suspend = kszphy_suspend, - .resume = kszphy_resume, + .suspend = genphy_suspend, + .resume = genphy_resume, }, { .phy_id = PHY_ID_KSZ9021, .phy_id_mask = 0x000ffffe, -- cgit v1.2.3 From 15f03ffe4bb951e982457f44b6cf6b06ef4cbb93 Mon Sep 17 00:00:00 2001 From: Fabio Estevam Date: Wed, 4 May 2022 11:31:04 -0300 Subject: net: phy: micrel: Pass .probe for KS8737 Since commit f1131b9c23fb ("net: phy: micrel: use kszphy_suspend()/kszphy_resume for irq aware devices") the kszphy_suspend/ resume hooks are used. These functions require the probe function to be called so that priv can be allocated. Otherwise, a NULL pointer dereference happens inside kszphy_config_reset(). Cc: stable@vger.kernel.org Fixes: f1131b9c23fb ("net: phy: micrel: use kszphy_suspend()/kszphy_resume for irq aware devices") Reported-by: Andrew Lunn Signed-off-by: Fabio Estevam Reviewed-by: Andrew Lunn Link: https://lore.kernel.org/r/20220504143104.1286960-2-festevam@gmail.com Signed-off-by: Jakub Kicinski --- drivers/net/phy/micrel.c | 1 + 1 file changed, 1 insertion(+) (limited to 'drivers/net/phy') diff --git a/drivers/net/phy/micrel.c b/drivers/net/phy/micrel.c index 7c243cedde9f..9d7dafed3931 100644 --- a/drivers/net/phy/micrel.c +++ b/drivers/net/phy/micrel.c @@ -2657,6 +2657,7 @@ static struct phy_driver ksphy_driver[] = { .name = "Micrel KS8737", /* PHY_BASIC_FEATURES */ .driver_data = &ks8737_type, + .probe = kszphy_probe, .config_init = kszphy_config_init, .config_intr = kszphy_config_intr, .handle_interrupt = kszphy_handle_interrupt, -- cgit v1.2.3 From 91a7cda1f4b8bdf770000a3b60640576dafe0cec Mon Sep 17 00:00:00 2001 From: Francesco Dolcini Date: Fri, 6 May 2022 08:08:15 +0200 Subject: net: phy: Fix race condition on link status change This fixes the following error caused by a race condition between phydev->adjust_link() and a MDIO transaction in the phy interrupt handler. The issue was reproduced with the ethernet FEC driver and a micrel KSZ9031 phy. [ 146.195696] fec 2188000.ethernet eth0: MDIO read timeout [ 146.201779] ------------[ cut here ]------------ [ 146.206671] WARNING: CPU: 0 PID: 571 at drivers/net/phy/phy.c:942 phy_error+0x24/0x6c [ 146.214744] Modules linked in: bnep imx_vdoa imx_sdma evbug [ 146.220640] CPU: 0 PID: 571 Comm: irq/128-2188000 Not tainted 5.18.0-rc3-00080-gd569e86915b7 #9 [ 146.229563] Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree) [ 146.236257] unwind_backtrace from show_stack+0x10/0x14 [ 146.241640] show_stack from dump_stack_lvl+0x58/0x70 [ 146.246841] dump_stack_lvl from __warn+0xb4/0x24c [ 146.251772] __warn from warn_slowpath_fmt+0x5c/0xd4 [ 146.256873] warn_slowpath_fmt from phy_error+0x24/0x6c [ 146.262249] phy_error from kszphy_handle_interrupt+0x40/0x48 [ 146.268159] kszphy_handle_interrupt from irq_thread_fn+0x1c/0x78 [ 146.274417] irq_thread_fn from irq_thread+0xf0/0x1dc [ 146.279605] irq_thread from kthread+0xe4/0x104 [ 146.284267] kthread from ret_from_fork+0x14/0x28 [ 146.289164] Exception stack(0xe6fa1fb0 to 0xe6fa1ff8) [ 146.294448] 1fa0: 00000000 00000000 00000000 00000000 [ 146.302842] 1fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 [ 146.311281] 1fe0: 00000000 00000000 00000000 00000000 00000013 00000000 [ 146.318262] irq event stamp: 12325 [ 146.321780] hardirqs last enabled at (12333): [] __up_console_sem+0x50/0x60 [ 146.330013] hardirqs last disabled at (12342): [] __up_console_sem+0x3c/0x60 [ 146.338259] softirqs last enabled at (12324): [] __do_softirq+0x2c0/0x624 [ 146.346311] softirqs last disabled at (12319): [] __irq_exit_rcu+0x138/0x178 [ 146.354447] ---[ end trace 0000000000000000 ]--- With the FEC driver phydev->adjust_link() calls fec_enet_adjust_link() calls fec_stop()/fec_restart() and both these function reset and temporary disable the FEC disrupting any MII transaction that could be happening at the same time. fec_enet_adjust_link() and phy_read() can be running at the same time when we have one additional interrupt before the phy_state_machine() is able to terminate. Thread 1 (phylib WQ) | Thread 2 (phy interrupt) | | phy_interrupt() <-- PHY IRQ | handle_interrupt() | phy_read() | phy_trigger_machine() | --> schedule phylib WQ | | phy_state_machine() | phy_check_link_status() | phy_link_change() | phydev->adjust_link() | fec_enet_adjust_link() | --> FEC reset | phy_interrupt() <-- PHY IRQ | phy_read() | Fix this by acquiring the phydev lock in phy_interrupt(). Link: https://lore.kernel.org/all/20220422152612.GA510015@francesco-nb.int.toradex.com/ Fixes: c974bdbc3e77 ("net: phy: Use threaded IRQ, to allow IRQ from sleeping devices") cc: Signed-off-by: Francesco Dolcini Reviewed-by: Andrew Lunn Link: https://lore.kernel.org/r/20220506060815.327382-1-francesco.dolcini@toradex.com Signed-off-by: Jakub Kicinski --- drivers/net/phy/phy.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'drivers/net/phy') diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c index beb2b66da132..f122026c4682 100644 --- a/drivers/net/phy/phy.c +++ b/drivers/net/phy/phy.c @@ -970,8 +970,13 @@ static irqreturn_t phy_interrupt(int irq, void *phy_dat) { struct phy_device *phydev = phy_dat; struct phy_driver *drv = phydev->drv; + irqreturn_t ret; - return drv->handle_interrupt(phydev); + mutex_lock(&phydev->lock); + ret = drv->handle_interrupt(phydev); + mutex_unlock(&phydev->lock); + + return ret; } /** -- cgit v1.2.3 From 12a4d677b1c34717443470c1492fe520638ef39a Mon Sep 17 00:00:00 2001 From: Wan Jiabing Date: Mon, 9 May 2022 22:45:19 +0800 Subject: net: phy: micrel: Fix incorrect variable type in micrel In lanphy_read_page_reg, calling __phy_read() might return a negative error code. Use 'int' to check the error code. Fixes: 7c2dcfa295b1 ("net: phy: micrel: Add support for LAN8804 PHY") Signed-off-by: Wan Jiabing Reviewed-by: Andrew Lunn Link: https://lore.kernel.org/r/20220509144519.2343399-1-wanjiabing@vivo.com Signed-off-by: Jakub Kicinski --- drivers/net/phy/micrel.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) (limited to 'drivers/net/phy') diff --git a/drivers/net/phy/micrel.c b/drivers/net/phy/micrel.c index 9d7dafed3931..cd9aa353b653 100644 --- a/drivers/net/phy/micrel.c +++ b/drivers/net/phy/micrel.c @@ -1743,7 +1743,7 @@ static int ksz886x_cable_test_get_status(struct phy_device *phydev, static int lanphy_read_page_reg(struct phy_device *phydev, int page, u32 addr) { - u32 data; + int data; phy_lock_mdio_bus(phydev); __phy_write(phydev, LAN_EXT_PAGE_ACCESS_CONTROL, page); @@ -2444,8 +2444,7 @@ static int lan8804_config_init(struct phy_device *phydev) static irqreturn_t lan8814_handle_interrupt(struct phy_device *phydev) { - u16 tsu_irq_status; - int irq_status; + int irq_status, tsu_irq_status; irq_status = phy_read(phydev, LAN8814_INTS); if (irq_status > 0 && (irq_status & LAN8814_INT_LINK)) -- cgit v1.2.3