From a5feba71ec9c14a54c3babdc732c5b6866d8ee43 Mon Sep 17 00:00:00 2001 From: Douglas Anderson Date: Fri, 20 Oct 2023 14:06:52 -0700 Subject: [PATCH 1/8] r8152: Increase USB control msg timeout to 5000ms as per spec According to the comment next to USB_CTRL_GET_TIMEOUT and USB_CTRL_SET_TIMEOUT, although sending/receiving control messages is usually quite fast, the spec allows them to take up to 5 seconds. Let's increase the timeout in the Realtek driver from 500ms to 5000ms (using the #defines) to account for this. This is not just a theoretical change. The need for the longer timeout was seen in testing. Specifically, if you drop a sc7180-trogdor based Chromebook into the kdb debugger and then "go" again after sitting in the debugger for a while, the next USB control message takes a long time. Out of ~40 tests the slowest USB control message was 4.5 seconds. While dropping into kdb is not exactly an end-user scenario, the above is similar to what could happen due to an temporary interrupt storm, what could happen if there was a host controller (HW or SW) issue, or what could happen if the Realtek device got into a confused state and needed time to recover. This change is fairly critical since the r8152 driver in Linux doesn't expect register reads/writes (which are backed by USB control messages) to fail. Fixes: ac718b69301c ("net/usb: new driver for RTL8152") Suggested-by: Hayes Wang Signed-off-by: Douglas Anderson Reviewed-by: Grant Grundler Signed-off-by: David S. Miller --- drivers/net/usb/r8152.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/net/usb/r8152.c b/drivers/net/usb/r8152.c index 0c13d9950cd85..482957beae66b 100644 --- a/drivers/net/usb/r8152.c +++ b/drivers/net/usb/r8152.c @@ -1212,7 +1212,7 @@ int get_registers(struct r8152 *tp, u16 value, u16 index, u16 size, void *data) ret = usb_control_msg(tp->udev, tp->pipe_ctrl_in, RTL8152_REQ_GET_REGS, RTL8152_REQT_READ, - value, index, tmp, size, 500); + value, index, tmp, size, USB_CTRL_GET_TIMEOUT); if (ret < 0) memset(data, 0xff, size); else @@ -1235,7 +1235,7 @@ int set_registers(struct r8152 *tp, u16 value, u16 index, u16 size, void *data) ret = usb_control_msg(tp->udev, tp->pipe_ctrl_out, RTL8152_REQ_SET_REGS, RTL8152_REQT_WRITE, - value, index, tmp, size, 500); + value, index, tmp, size, USB_CTRL_SET_TIMEOUT); kfree(tmp); @@ -9494,7 +9494,8 @@ static u8 __rtl_get_hw_ver(struct usb_device *udev) ret = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0), RTL8152_REQ_GET_REGS, RTL8152_REQT_READ, - PLA_TCR0, MCU_TYPE_PLA, tmp, sizeof(*tmp), 500); + PLA_TCR0, MCU_TYPE_PLA, tmp, sizeof(*tmp), + USB_CTRL_GET_TIMEOUT); if (ret > 0) ocp_data = (__le32_to_cpu(*tmp) >> 16) & VERSION_MASK; From 5dd17689526971c5ae12bc8398f34bd68cd0499e Mon Sep 17 00:00:00 2001 From: Douglas Anderson Date: Fri, 20 Oct 2023 14:06:53 -0700 Subject: [PATCH 2/8] r8152: Run the unload routine if we have errors during probe The rtl8152_probe() function lacks a call to the chip-specific unload() routine when it sees an error in probe. Add it in to match the cleanup code in rtl8152_disconnect(). Fixes: ac718b69301c ("net/usb: new driver for RTL8152") Signed-off-by: Douglas Anderson Reviewed-by: Grant Grundler Signed-off-by: David S. Miller --- drivers/net/usb/r8152.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/net/usb/r8152.c b/drivers/net/usb/r8152.c index 482957beae66b..201c688e3e3f5 100644 --- a/drivers/net/usb/r8152.c +++ b/drivers/net/usb/r8152.c @@ -9783,6 +9783,8 @@ static int rtl8152_probe(struct usb_interface *intf, out1: tasklet_kill(&tp->tx_tl); + if (tp->rtl_ops.unload) + tp->rtl_ops.unload(tp); usb_set_intfdata(intf, NULL); out: free_netdev(netdev); From bb8adff9123e492598162ac1baad01a53891aef6 Mon Sep 17 00:00:00 2001 From: Douglas Anderson Date: Fri, 20 Oct 2023 14:06:54 -0700 Subject: [PATCH 3/8] r8152: Cancel hw_phy_work if we have an error in probe The error handling in rtl8152_probe() is missing a call to cancel the hw_phy_work. Add it in to match what's in the cleanup code in rtl8152_disconnect(). Fixes: a028a9e003f2 ("r8152: move the settings of PHY to a work queue") Signed-off-by: Douglas Anderson Reviewed-by: Grant Grundler Signed-off-by: David S. Miller --- drivers/net/usb/r8152.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/net/usb/r8152.c b/drivers/net/usb/r8152.c index 201c688e3e3f5..d10b0886b6520 100644 --- a/drivers/net/usb/r8152.c +++ b/drivers/net/usb/r8152.c @@ -9783,6 +9783,7 @@ static int rtl8152_probe(struct usb_interface *intf, out1: tasklet_kill(&tp->tx_tl); + cancel_delayed_work_sync(&tp->hw_phy_work); if (tp->rtl_ops.unload) tp->rtl_ops.unload(tp); usb_set_intfdata(intf, NULL); From b8d35024d4059ca550cba11ac9ab23a6c238d929 Mon Sep 17 00:00:00 2001 From: Douglas Anderson Date: Fri, 20 Oct 2023 14:06:55 -0700 Subject: [PATCH 4/8] r8152: Release firmware if we have an error in probe The error handling in rtl8152_probe() is missing a call to release firmware. Add it in to match what's in the cleanup code in rtl8152_disconnect(). Fixes: 9370f2d05a2a ("r8152: support request_firmware for RTL8153") Signed-off-by: Douglas Anderson Reviewed-by: Grant Grundler Signed-off-by: David S. Miller --- drivers/net/usb/r8152.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/net/usb/r8152.c b/drivers/net/usb/r8152.c index d10b0886b6520..656fe90734fce 100644 --- a/drivers/net/usb/r8152.c +++ b/drivers/net/usb/r8152.c @@ -9786,6 +9786,7 @@ static int rtl8152_probe(struct usb_interface *intf, cancel_delayed_work_sync(&tp->hw_phy_work); if (tp->rtl_ops.unload) tp->rtl_ops.unload(tp); + rtl8152_release_firmware(tp); usb_set_intfdata(intf, NULL); out: free_netdev(netdev); From dc90ba37a8c37042407fa6970b9830890cfe6047 Mon Sep 17 00:00:00 2001 From: Douglas Anderson Date: Fri, 20 Oct 2023 14:06:56 -0700 Subject: [PATCH 5/8] r8152: Check for unplug in rtl_phy_patch_request() If the adapter is unplugged while we're looping in rtl_phy_patch_request() we could end up looping for 10 seconds (2 ms * 5000 loops). Add code similar to what's done in other places in the driver to check for unplug and bail. Signed-off-by: Douglas Anderson Reviewed-by: Grant Grundler Signed-off-by: David S. Miller --- drivers/net/usb/r8152.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/net/usb/r8152.c b/drivers/net/usb/r8152.c index 656fe90734fce..9888bc43e9038 100644 --- a/drivers/net/usb/r8152.c +++ b/drivers/net/usb/r8152.c @@ -4046,6 +4046,9 @@ static int rtl_phy_patch_request(struct r8152 *tp, bool request, bool wait) for (i = 0; wait && i < 5000; i++) { u32 ocp_data; + if (test_bit(RTL8152_UNPLUG, &tp->flags)) + break; + usleep_range(1000, 2000); ocp_data = ocp_reg_read(tp, OCP_PHY_PATCH_STAT); if ((ocp_data & PATCH_READY) ^ check) From bc65cc42af737a5a35f83842408ef2c6c79ba025 Mon Sep 17 00:00:00 2001 From: Douglas Anderson Date: Fri, 20 Oct 2023 14:06:57 -0700 Subject: [PATCH 6/8] r8152: Check for unplug in r8153b_ups_en() / r8153c_ups_en() If the adapter is unplugged while we're looping in r8153b_ups_en() / r8153c_ups_en() we could end up looping for 10 seconds (20 ms * 500 loops). Add code similar to what's done in other places in the driver to check for unplug and bail. Signed-off-by: Douglas Anderson Reviewed-by: Grant Grundler Signed-off-by: David S. Miller --- drivers/net/usb/r8152.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/net/usb/r8152.c b/drivers/net/usb/r8152.c index 9888bc43e9038..982f9ca03e7a6 100644 --- a/drivers/net/usb/r8152.c +++ b/drivers/net/usb/r8152.c @@ -3663,6 +3663,8 @@ static void r8153b_ups_en(struct r8152 *tp, bool enable) int i; for (i = 0; i < 500; i++) { + if (test_bit(RTL8152_UNPLUG, &tp->flags)) + return; if (ocp_read_word(tp, MCU_TYPE_PLA, PLA_BOOT_CTRL) & AUTOLOAD_DONE) break; @@ -3703,6 +3705,8 @@ static void r8153c_ups_en(struct r8152 *tp, bool enable) int i; for (i = 0; i < 500; i++) { + if (test_bit(RTL8152_UNPLUG, &tp->flags)) + return; if (ocp_read_word(tp, MCU_TYPE_PLA, PLA_BOOT_CTRL) & AUTOLOAD_DONE) break; From 715f67f33af45ce2cc3a5b1ef133cc8c8e7787b0 Mon Sep 17 00:00:00 2001 From: Douglas Anderson Date: Fri, 20 Oct 2023 14:06:58 -0700 Subject: [PATCH 7/8] r8152: Rename RTL8152_UNPLUG to RTL8152_INACCESSIBLE Whenever the RTL8152_UNPLUG is set that just tells the driver that all accesses will fail and we should just immediately bail. A future patch will use this same concept at a time when the driver hasn't actually been unplugged but is about to be reset. Rename the flag in preparation for the future patch. This is a no-op change and just a search and replace. Signed-off-by: Douglas Anderson Reviewed-by: Grant Grundler Signed-off-by: David S. Miller --- drivers/net/usb/r8152.c | 96 ++++++++++++++++++++--------------------- 1 file changed, 48 insertions(+), 48 deletions(-) diff --git a/drivers/net/usb/r8152.c b/drivers/net/usb/r8152.c index 982f9ca03e7a6..65232848b31d5 100644 --- a/drivers/net/usb/r8152.c +++ b/drivers/net/usb/r8152.c @@ -764,7 +764,7 @@ enum rtl_register_content { /* rtl8152 flags */ enum rtl8152_flags { - RTL8152_UNPLUG = 0, + RTL8152_INACCESSIBLE = 0, RTL8152_SET_RX_MODE, WORK_ENABLE, RTL8152_LINK_CHG, @@ -1245,7 +1245,7 @@ int set_registers(struct r8152 *tp, u16 value, u16 index, u16 size, void *data) static void rtl_set_unplug(struct r8152 *tp) { if (tp->udev->state == USB_STATE_NOTATTACHED) { - set_bit(RTL8152_UNPLUG, &tp->flags); + set_bit(RTL8152_INACCESSIBLE, &tp->flags); smp_mb__after_atomic(); } } @@ -1256,7 +1256,7 @@ static int generic_ocp_read(struct r8152 *tp, u16 index, u16 size, u16 limit = 64; int ret = 0; - if (test_bit(RTL8152_UNPLUG, &tp->flags)) + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) return -ENODEV; /* both size and indix must be 4 bytes align */ @@ -1300,7 +1300,7 @@ static int generic_ocp_write(struct r8152 *tp, u16 index, u16 byteen, u16 byteen_start, byteen_end, byen; u16 limit = 512; - if (test_bit(RTL8152_UNPLUG, &tp->flags)) + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) return -ENODEV; /* both size and indix must be 4 bytes align */ @@ -1537,7 +1537,7 @@ static int read_mii_word(struct net_device *netdev, int phy_id, int reg) struct r8152 *tp = netdev_priv(netdev); int ret; - if (test_bit(RTL8152_UNPLUG, &tp->flags)) + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) return -ENODEV; if (phy_id != R8152_PHY_ID) @@ -1553,7 +1553,7 @@ void write_mii_word(struct net_device *netdev, int phy_id, int reg, int val) { struct r8152 *tp = netdev_priv(netdev); - if (test_bit(RTL8152_UNPLUG, &tp->flags)) + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) return; if (phy_id != R8152_PHY_ID) @@ -1758,7 +1758,7 @@ static void read_bulk_callback(struct urb *urb) if (!tp) return; - if (test_bit(RTL8152_UNPLUG, &tp->flags)) + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) return; if (!test_bit(WORK_ENABLE, &tp->flags)) @@ -1850,7 +1850,7 @@ static void write_bulk_callback(struct urb *urb) if (!test_bit(WORK_ENABLE, &tp->flags)) return; - if (test_bit(RTL8152_UNPLUG, &tp->flags)) + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) return; if (!skb_queue_empty(&tp->tx_queue)) @@ -1871,7 +1871,7 @@ static void intr_callback(struct urb *urb) if (!test_bit(WORK_ENABLE, &tp->flags)) return; - if (test_bit(RTL8152_UNPLUG, &tp->flags)) + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) return; switch (status) { @@ -2615,7 +2615,7 @@ static void bottom_half(struct tasklet_struct *t) { struct r8152 *tp = from_tasklet(tp, t, tx_tl); - if (test_bit(RTL8152_UNPLUG, &tp->flags)) + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) return; if (!test_bit(WORK_ENABLE, &tp->flags)) @@ -2658,7 +2658,7 @@ int r8152_submit_rx(struct r8152 *tp, struct rx_agg *agg, gfp_t mem_flags) int ret; /* The rx would be stopped, so skip submitting */ - if (test_bit(RTL8152_UNPLUG, &tp->flags) || + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags) || !test_bit(WORK_ENABLE, &tp->flags) || !netif_carrier_ok(tp->netdev)) return 0; @@ -3058,7 +3058,7 @@ static int rtl_enable(struct r8152 *tp) static int rtl8152_enable(struct r8152 *tp) { - if (test_bit(RTL8152_UNPLUG, &tp->flags)) + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) return -ENODEV; set_tx_qlen(tp); @@ -3145,7 +3145,7 @@ static int rtl8153_enable(struct r8152 *tp) { u32 ocp_data; - if (test_bit(RTL8152_UNPLUG, &tp->flags)) + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) return -ENODEV; set_tx_qlen(tp); @@ -3177,7 +3177,7 @@ static void rtl_disable(struct r8152 *tp) u32 ocp_data; int i; - if (test_bit(RTL8152_UNPLUG, &tp->flags)) { + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) { rtl_drop_queued_tx(tp); return; } @@ -3631,7 +3631,7 @@ static u16 r8153_phy_status(struct r8152 *tp, u16 desired) } msleep(20); - if (test_bit(RTL8152_UNPLUG, &tp->flags)) + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) break; } @@ -3663,7 +3663,7 @@ static void r8153b_ups_en(struct r8152 *tp, bool enable) int i; for (i = 0; i < 500; i++) { - if (test_bit(RTL8152_UNPLUG, &tp->flags)) + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) return; if (ocp_read_word(tp, MCU_TYPE_PLA, PLA_BOOT_CTRL) & AUTOLOAD_DONE) @@ -3705,7 +3705,7 @@ static void r8153c_ups_en(struct r8152 *tp, bool enable) int i; for (i = 0; i < 500; i++) { - if (test_bit(RTL8152_UNPLUG, &tp->flags)) + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) return; if (ocp_read_word(tp, MCU_TYPE_PLA, PLA_BOOT_CTRL) & AUTOLOAD_DONE) @@ -4050,8 +4050,8 @@ static int rtl_phy_patch_request(struct r8152 *tp, bool request, bool wait) for (i = 0; wait && i < 5000; i++) { u32 ocp_data; - if (test_bit(RTL8152_UNPLUG, &tp->flags)) - break; + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) + return -ENODEV; usleep_range(1000, 2000); ocp_data = ocp_reg_read(tp, OCP_PHY_PATCH_STAT); @@ -6009,7 +6009,7 @@ static int rtl8156_enable(struct r8152 *tp) u32 ocp_data; u16 speed; - if (test_bit(RTL8152_UNPLUG, &tp->flags)) + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) return -ENODEV; r8156_fc_parameter(tp); @@ -6067,7 +6067,7 @@ static int rtl8156b_enable(struct r8152 *tp) u32 ocp_data; u16 speed; - if (test_bit(RTL8152_UNPLUG, &tp->flags)) + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) return -ENODEV; set_tx_qlen(tp); @@ -6253,7 +6253,7 @@ static int rtl8152_set_speed(struct r8152 *tp, u8 autoneg, u32 speed, u8 duplex, static void rtl8152_up(struct r8152 *tp) { - if (test_bit(RTL8152_UNPLUG, &tp->flags)) + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) return; r8152_aldps_en(tp, false); @@ -6263,7 +6263,7 @@ static void rtl8152_up(struct r8152 *tp) static void rtl8152_down(struct r8152 *tp) { - if (test_bit(RTL8152_UNPLUG, &tp->flags)) { + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) { rtl_drop_queued_tx(tp); return; } @@ -6278,7 +6278,7 @@ static void rtl8153_up(struct r8152 *tp) { u32 ocp_data; - if (test_bit(RTL8152_UNPLUG, &tp->flags)) + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) return; r8153_u1u2en(tp, false); @@ -6318,7 +6318,7 @@ static void rtl8153_down(struct r8152 *tp) { u32 ocp_data; - if (test_bit(RTL8152_UNPLUG, &tp->flags)) { + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) { rtl_drop_queued_tx(tp); return; } @@ -6339,7 +6339,7 @@ static void rtl8153b_up(struct r8152 *tp) { u32 ocp_data; - if (test_bit(RTL8152_UNPLUG, &tp->flags)) + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) return; r8153b_u1u2en(tp, false); @@ -6363,7 +6363,7 @@ static void rtl8153b_down(struct r8152 *tp) { u32 ocp_data; - if (test_bit(RTL8152_UNPLUG, &tp->flags)) { + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) { rtl_drop_queued_tx(tp); return; } @@ -6400,7 +6400,7 @@ static void rtl8153c_up(struct r8152 *tp) { u32 ocp_data; - if (test_bit(RTL8152_UNPLUG, &tp->flags)) + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) return; r8153b_u1u2en(tp, false); @@ -6481,7 +6481,7 @@ static void rtl8156_up(struct r8152 *tp) { u32 ocp_data; - if (test_bit(RTL8152_UNPLUG, &tp->flags)) + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) return; r8153b_u1u2en(tp, false); @@ -6554,7 +6554,7 @@ static void rtl8156_down(struct r8152 *tp) { u32 ocp_data; - if (test_bit(RTL8152_UNPLUG, &tp->flags)) { + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) { rtl_drop_queued_tx(tp); return; } @@ -6692,7 +6692,7 @@ static void rtl_work_func_t(struct work_struct *work) /* If the device is unplugged or !netif_running(), the workqueue * doesn't need to wake the device, and could return directly. */ - if (test_bit(RTL8152_UNPLUG, &tp->flags) || !netif_running(tp->netdev)) + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags) || !netif_running(tp->netdev)) return; if (usb_autopm_get_interface(tp->intf) < 0) @@ -6731,7 +6731,7 @@ static void rtl_hw_phy_work_func_t(struct work_struct *work) { struct r8152 *tp = container_of(work, struct r8152, hw_phy_work.work); - if (test_bit(RTL8152_UNPLUG, &tp->flags)) + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) return; if (usb_autopm_get_interface(tp->intf) < 0) @@ -6858,7 +6858,7 @@ static int rtl8152_close(struct net_device *netdev) netif_stop_queue(netdev); res = usb_autopm_get_interface(tp->intf); - if (res < 0 || test_bit(RTL8152_UNPLUG, &tp->flags)) { + if (res < 0 || test_bit(RTL8152_INACCESSIBLE, &tp->flags)) { rtl_drop_queued_tx(tp); rtl_stop_rx(tp); } else { @@ -6891,7 +6891,7 @@ static void r8152b_init(struct r8152 *tp) u32 ocp_data; u16 data; - if (test_bit(RTL8152_UNPLUG, &tp->flags)) + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) return; data = r8152_mdio_read(tp, MII_BMCR); @@ -6935,7 +6935,7 @@ static void r8153_init(struct r8152 *tp) u16 data; int i; - if (test_bit(RTL8152_UNPLUG, &tp->flags)) + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) return; r8153_u1u2en(tp, false); @@ -6946,7 +6946,7 @@ static void r8153_init(struct r8152 *tp) break; msleep(20); - if (test_bit(RTL8152_UNPLUG, &tp->flags)) + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) break; } @@ -7075,7 +7075,7 @@ static void r8153b_init(struct r8152 *tp) u16 data; int i; - if (test_bit(RTL8152_UNPLUG, &tp->flags)) + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) return; r8153b_u1u2en(tp, false); @@ -7086,7 +7086,7 @@ static void r8153b_init(struct r8152 *tp) break; msleep(20); - if (test_bit(RTL8152_UNPLUG, &tp->flags)) + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) break; } @@ -7157,7 +7157,7 @@ static void r8153c_init(struct r8152 *tp) u16 data; int i; - if (test_bit(RTL8152_UNPLUG, &tp->flags)) + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) return; r8153b_u1u2en(tp, false); @@ -7177,7 +7177,7 @@ static void r8153c_init(struct r8152 *tp) break; msleep(20); - if (test_bit(RTL8152_UNPLUG, &tp->flags)) + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) return; } @@ -8006,7 +8006,7 @@ static void r8156_init(struct r8152 *tp) u16 data; int i; - if (test_bit(RTL8152_UNPLUG, &tp->flags)) + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) return; ocp_data = ocp_read_byte(tp, MCU_TYPE_USB, USB_ECM_OP); @@ -8027,7 +8027,7 @@ static void r8156_init(struct r8152 *tp) break; msleep(20); - if (test_bit(RTL8152_UNPLUG, &tp->flags)) + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) return; } @@ -8102,7 +8102,7 @@ static void r8156b_init(struct r8152 *tp) u16 data; int i; - if (test_bit(RTL8152_UNPLUG, &tp->flags)) + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) return; ocp_data = ocp_read_byte(tp, MCU_TYPE_USB, USB_ECM_OP); @@ -8136,7 +8136,7 @@ static void r8156b_init(struct r8152 *tp) break; msleep(20); - if (test_bit(RTL8152_UNPLUG, &tp->flags)) + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) return; } @@ -9165,7 +9165,7 @@ static int rtl8152_ioctl(struct net_device *netdev, struct ifreq *rq, int cmd) struct mii_ioctl_data *data = if_mii(rq); int res; - if (test_bit(RTL8152_UNPLUG, &tp->flags)) + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) return -ENODEV; res = usb_autopm_get_interface(tp->intf); @@ -9267,7 +9267,7 @@ static const struct net_device_ops rtl8152_netdev_ops = { static void rtl8152_unload(struct r8152 *tp) { - if (test_bit(RTL8152_UNPLUG, &tp->flags)) + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) return; if (tp->version != RTL_VER_01) @@ -9276,7 +9276,7 @@ static void rtl8152_unload(struct r8152 *tp) static void rtl8153_unload(struct r8152 *tp) { - if (test_bit(RTL8152_UNPLUG, &tp->flags)) + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) return; r8153_power_cut_en(tp, false); @@ -9284,7 +9284,7 @@ static void rtl8153_unload(struct r8152 *tp) static void rtl8153b_unload(struct r8152 *tp) { - if (test_bit(RTL8152_UNPLUG, &tp->flags)) + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) return; r8153b_power_cut_en(tp, false); From d9962b0d42029bcb40fe3c38bce06d1870fa4df4 Mon Sep 17 00:00:00 2001 From: Douglas Anderson Date: Fri, 20 Oct 2023 14:06:59 -0700 Subject: [PATCH 8/8] r8152: Block future register access if register access fails Even though the functions to read/write registers can fail, most of the places in the r8152 driver that read/write register values don't check error codes. The lack of error code checking is problematic in at least two ways. The first problem is that the r8152 driver often uses code patterns similar to this: x = read_register() x = x | SOME_BIT; write_register(x); ...with the above pattern, if the read_register() fails and returns garbage then we'll end up trying to write modified garbage back to the Realtek adapter. If the write_register() succeeds that's bad. Note that as of commit f53a7ad18959 ("r8152: Set memory to all 0xFFs on failed reg reads") the "garbage" returned by read_register() will at least be consistent garbage, but it is still garbage. It turns out that this problem is very serious. Writing garbage to some of the hardware registers on the Ethernet adapter can put the adapter in such a bad state that it needs to be power cycled (fully unplugged and plugged in again) before it can enumerate again. The second problem is that the r8152 driver generally has functions that are long sequences of register writes. Assuming everything will be OK if a random register write fails in the middle isn't a great assumption. One might wonder if the above two problems are real. You could ask if we would really have a successful write after a failed read. It turns out that the answer appears to be "yes, this can happen". In fact, we've seen at least two distinct failure modes where this happens. On a sc7180-trogdor Chromebook if you drop into kdb for a while and then resume, you can see: 1. We get a "Tx timeout" 2. The "Tx timeout" queues up a USB reset. 3. In rtl8152_pre_reset() we try to reinit the hardware. 4. The first several (2-9) register accesses fail with a timeout, then things recover. The above test case was actually fixed by the patch ("r8152: Increase USB control msg timeout to 5000ms as per spec") but at least shows that we really can see successful calls after failed ones. On a different (AMD) based Chromebook with a particular adapter, we found that during reboot tests we'd also sometimes get a transitory failure. In this case we saw -EPIPE being returned sometimes. Retrying worked, but retrying is not always safe for all register accesses since reading/writing some registers might have side effects (like registers that clear on read). Let's fully lock out all register access if a register access fails. When we do this, we'll try to queue up a USB reset and try to unlock register access after the reset. This is slightly tricker than it sounds since the r8152 driver has an optimized reset sequence that only works reliably after probe happens. In order to handle this, we avoid the optimized reset if probe didn't finish. Instead, we simply retry the probe routine in this case. When locking out access, we'll use the existing infrastructure that the driver was using when it detected we were unplugged. This keeps us from getting stuck in delay loops in some parts of the driver. Signed-off-by: Douglas Anderson Reviewed-by: Grant Grundler Signed-off-by: David S. Miller --- drivers/net/usb/r8152.c | 207 ++++++++++++++++++++++++++++++++++------ 1 file changed, 176 insertions(+), 31 deletions(-) diff --git a/drivers/net/usb/r8152.c b/drivers/net/usb/r8152.c index 65232848b31d5..afb20c0ed688d 100644 --- a/drivers/net/usb/r8152.c +++ b/drivers/net/usb/r8152.c @@ -773,6 +773,9 @@ enum rtl8152_flags { SCHEDULE_TASKLET, GREEN_ETHERNET, RX_EPROTO, + IN_PRE_RESET, + PROBED_WITH_NO_ERRORS, + PROBE_SHOULD_RETRY, }; #define DEVICE_ID_LENOVO_USB_C_TRAVEL_HUB 0x721e @@ -953,6 +956,8 @@ struct r8152 { u8 version; u8 duplex; u8 autoneg; + + unsigned int reg_access_reset_count; }; /** @@ -1200,6 +1205,96 @@ static unsigned int agg_buf_sz = 16384; #define RTL_LIMITED_TSO_SIZE (size_to_mtu(agg_buf_sz) - sizeof(struct tx_desc)) +/* If register access fails then we block access and issue a reset. If this + * happens too many times in a row without a successful access then we stop + * trying to reset and just leave access blocked. + */ +#define REGISTER_ACCESS_MAX_RESETS 3 + +static void rtl_set_inaccessible(struct r8152 *tp) +{ + set_bit(RTL8152_INACCESSIBLE, &tp->flags); + smp_mb__after_atomic(); +} + +static void rtl_set_accessible(struct r8152 *tp) +{ + clear_bit(RTL8152_INACCESSIBLE, &tp->flags); + smp_mb__after_atomic(); +} + +static +int r8152_control_msg(struct r8152 *tp, unsigned int pipe, __u8 request, + __u8 requesttype, __u16 value, __u16 index, void *data, + __u16 size, const char *msg_tag) +{ + struct usb_device *udev = tp->udev; + int ret; + + if (test_bit(RTL8152_INACCESSIBLE, &tp->flags)) + return -ENODEV; + + ret = usb_control_msg(udev, pipe, request, requesttype, + value, index, data, size, + USB_CTRL_GET_TIMEOUT); + + /* No need to issue a reset to report an error if the USB device got + * unplugged; just return immediately. + */ + if (ret == -ENODEV) + return ret; + + /* If the write was successful then we're done */ + if (ret >= 0) { + tp->reg_access_reset_count = 0; + return ret; + } + + dev_err(&udev->dev, + "Failed to %s %d bytes at %#06x/%#06x (%d)\n", + msg_tag, size, value, index, ret); + + /* Block all future register access until we reset. Much of the code + * in the driver doesn't check for errors. Notably, many parts of the + * driver do a read/modify/write of a register value without + * confirming that the read succeeded. Writing back modified garbage + * like this can fully wedge the adapter, requiring a power cycle. + */ + rtl_set_inaccessible(tp); + + /* If probe hasn't yet finished, then we'll request a retry of the + * whole probe routine if we get any control transfer errors. We + * never have to clear this bit since we free/reallocate the whole "tp" + * structure if we retry probe. + */ + if (!test_bit(PROBED_WITH_NO_ERRORS, &tp->flags)) { + set_bit(PROBE_SHOULD_RETRY, &tp->flags); + return ret; + } + + /* Failing to access registers in pre-reset is not surprising since we + * wouldn't be resetting if things were behaving normally. The register + * access we do in pre-reset isn't truly mandatory--we're just reusing + * the disable() function and trying to be nice by powering the + * adapter down before resetting it. Thus, if we're in pre-reset, + * we'll return right away and not try to queue up yet another reset. + * We know the post-reset is already coming. + */ + if (test_bit(IN_PRE_RESET, &tp->flags)) + return ret; + + if (tp->reg_access_reset_count < REGISTER_ACCESS_MAX_RESETS) { + usb_queue_reset_device(tp->intf); + tp->reg_access_reset_count++; + } else if (tp->reg_access_reset_count == REGISTER_ACCESS_MAX_RESETS) { + dev_err(&udev->dev, + "Tried to reset %d times; giving up.\n", + REGISTER_ACCESS_MAX_RESETS); + } + + return ret; +} + static int get_registers(struct r8152 *tp, u16 value, u16 index, u16 size, void *data) { @@ -1210,9 +1305,10 @@ int get_registers(struct r8152 *tp, u16 value, u16 index, u16 size, void *data) if (!tmp) return -ENOMEM; - ret = usb_control_msg(tp->udev, tp->pipe_ctrl_in, - RTL8152_REQ_GET_REGS, RTL8152_REQT_READ, - value, index, tmp, size, USB_CTRL_GET_TIMEOUT); + ret = r8152_control_msg(tp, tp->pipe_ctrl_in, + RTL8152_REQ_GET_REGS, RTL8152_REQT_READ, + value, index, tmp, size, "read"); + if (ret < 0) memset(data, 0xff, size); else @@ -1233,9 +1329,9 @@ int set_registers(struct r8152 *tp, u16 value, u16 index, u16 size, void *data) if (!tmp) return -ENOMEM; - ret = usb_control_msg(tp->udev, tp->pipe_ctrl_out, - RTL8152_REQ_SET_REGS, RTL8152_REQT_WRITE, - value, index, tmp, size, USB_CTRL_SET_TIMEOUT); + ret = r8152_control_msg(tp, tp->pipe_ctrl_out, + RTL8152_REQ_SET_REGS, RTL8152_REQT_WRITE, + value, index, tmp, size, "write"); kfree(tmp); @@ -1244,10 +1340,8 @@ int set_registers(struct r8152 *tp, u16 value, u16 index, u16 size, void *data) static void rtl_set_unplug(struct r8152 *tp) { - if (tp->udev->state == USB_STATE_NOTATTACHED) { - set_bit(RTL8152_INACCESSIBLE, &tp->flags); - smp_mb__after_atomic(); - } + if (tp->udev->state == USB_STATE_NOTATTACHED) + rtl_set_inaccessible(tp); } static int generic_ocp_read(struct r8152 *tp, u16 index, u16 size, @@ -8262,7 +8356,7 @@ static int rtl8152_pre_reset(struct usb_interface *intf) struct r8152 *tp = usb_get_intfdata(intf); struct net_device *netdev; - if (!tp) + if (!tp || !test_bit(PROBED_WITH_NO_ERRORS, &tp->flags)) return 0; netdev = tp->netdev; @@ -8277,7 +8371,9 @@ static int rtl8152_pre_reset(struct usb_interface *intf) napi_disable(&tp->napi); if (netif_carrier_ok(netdev)) { mutex_lock(&tp->control); + set_bit(IN_PRE_RESET, &tp->flags); tp->rtl_ops.disable(tp); + clear_bit(IN_PRE_RESET, &tp->flags); mutex_unlock(&tp->control); } @@ -8290,9 +8386,11 @@ static int rtl8152_post_reset(struct usb_interface *intf) struct net_device *netdev; struct sockaddr sa; - if (!tp) + if (!tp || !test_bit(PROBED_WITH_NO_ERRORS, &tp->flags)) return 0; + rtl_set_accessible(tp); + /* reset the MAC address in case of policy change */ if (determine_ethernet_addr(tp, &sa) >= 0) { rtnl_lock(); @@ -9494,17 +9592,29 @@ static u8 __rtl_get_hw_ver(struct usb_device *udev) __le32 *tmp; u8 version; int ret; + int i; tmp = kmalloc(sizeof(*tmp), GFP_KERNEL); if (!tmp) return 0; - ret = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0), - RTL8152_REQ_GET_REGS, RTL8152_REQT_READ, - PLA_TCR0, MCU_TYPE_PLA, tmp, sizeof(*tmp), - USB_CTRL_GET_TIMEOUT); - if (ret > 0) - ocp_data = (__le32_to_cpu(*tmp) >> 16) & VERSION_MASK; + /* Retry up to 3 times in case there is a transitory error. We do this + * since retrying a read of the version is always safe and this + * function doesn't take advantage of r8152_control_msg(). + */ + for (i = 0; i < 3; i++) { + ret = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0), + RTL8152_REQ_GET_REGS, RTL8152_REQT_READ, + PLA_TCR0, MCU_TYPE_PLA, tmp, sizeof(*tmp), + USB_CTRL_GET_TIMEOUT); + if (ret > 0) { + ocp_data = (__le32_to_cpu(*tmp) >> 16) & VERSION_MASK; + break; + } + } + + if (i != 0 && ret > 0) + dev_warn(&udev->dev, "Needed %d retries to read version\n", i); kfree(tmp); @@ -9603,25 +9713,14 @@ static bool rtl8152_supports_lenovo_macpassthru(struct usb_device *udev) return 0; } -static int rtl8152_probe(struct usb_interface *intf, - const struct usb_device_id *id) +static int rtl8152_probe_once(struct usb_interface *intf, + const struct usb_device_id *id, u8 version) { struct usb_device *udev = interface_to_usbdev(intf); struct r8152 *tp; struct net_device *netdev; - u8 version; int ret; - if (intf->cur_altsetting->desc.bInterfaceClass != USB_CLASS_VENDOR_SPEC) - return -ENODEV; - - if (!rtl_check_vendor_ok(intf)) - return -ENODEV; - - version = rtl8152_get_version(intf); - if (version == RTL_VER_UNKNOWN) - return -ENODEV; - usb_reset_device(udev); netdev = alloc_etherdev(sizeof(struct r8152)); if (!netdev) { @@ -9784,10 +9883,20 @@ static int rtl8152_probe(struct usb_interface *intf, else device_set_wakeup_enable(&udev->dev, false); + /* If we saw a control transfer error while probing then we may + * want to try probe() again. Consider this an error. + */ + if (test_bit(PROBE_SHOULD_RETRY, &tp->flags)) + goto out2; + + set_bit(PROBED_WITH_NO_ERRORS, &tp->flags); netif_info(tp, probe, netdev, "%s\n", DRIVER_VERSION); return 0; +out2: + unregister_netdev(netdev); + out1: tasklet_kill(&tp->tx_tl); cancel_delayed_work_sync(&tp->hw_phy_work); @@ -9796,10 +9905,46 @@ static int rtl8152_probe(struct usb_interface *intf, rtl8152_release_firmware(tp); usb_set_intfdata(intf, NULL); out: + if (test_bit(PROBE_SHOULD_RETRY, &tp->flags)) + ret = -EAGAIN; + free_netdev(netdev); return ret; } +#define RTL8152_PROBE_TRIES 3 + +static int rtl8152_probe(struct usb_interface *intf, + const struct usb_device_id *id) +{ + u8 version; + int ret; + int i; + + if (intf->cur_altsetting->desc.bInterfaceClass != USB_CLASS_VENDOR_SPEC) + return -ENODEV; + + if (!rtl_check_vendor_ok(intf)) + return -ENODEV; + + version = rtl8152_get_version(intf); + if (version == RTL_VER_UNKNOWN) + return -ENODEV; + + for (i = 0; i < RTL8152_PROBE_TRIES; i++) { + ret = rtl8152_probe_once(intf, id, version); + if (ret != -EAGAIN) + break; + } + if (ret == -EAGAIN) { + dev_err(&intf->dev, + "r8152 failed probe after %d tries; giving up\n", i); + return -ENODEV; + } + + return ret; +} + static void rtl8152_disconnect(struct usb_interface *intf) { struct r8152 *tp = usb_get_intfdata(intf);