From 27600805e62f800bacf990354632eae4e487d34c Mon Sep 17 00:00:00 2001 From: Yazen Ghannam Date: Thu, 3 Sep 2026 10:43:25 -0500 Subject: x86/amd_node: Fix PCI device reference counting in amd_smn_init() The local "root" pointer is a temporary variable used during the device search. Therefore, refcount related to the search iterators should be cleaned up after the search is complete. Use the __free() cleanup macro to ensure the refcount is decremented when the temporary pointer goes out of scope. Additionally, increment the refcount when caching a root pointer. This ensures the in-use refcount is separate from the temporary search refcounting. Finally, drop the redundant "root = NULL" before the second search loop. The pci_get_class() iterator always decrements the refcount of its "from" argument, so the first loop can only fall through with "root" already NULL. Fixes: 0a4b61d9c2e4 ("x86/amd_node: Fix AMD root device caching") Closes: https://sashiko.dev/#/patchset/20260806160159.230453-1-jason.andryuk%40amd.com Reported-by: Sashiko Assisted-by: LLM Signed-off-by: Yazen Ghannam Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Mario Limonciello (AMD) Cc: Link: https://patch.msgid.link/20260903154325.74343-1-yazen.ghannam@amd.com --- drivers/net/arcnet/com20020.h | 132 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 132 insertions(+) create mode 100644 drivers/net/arcnet/com20020.h (limited to 'drivers/net/arcnet/com20020.h') diff --git a/drivers/net/arcnet/com20020.h b/drivers/net/arcnet/com20020.h new file mode 100644 index 000000000..68f49fdc2 --- /dev/null +++ b/drivers/net/arcnet/com20020.h @@ -0,0 +1,132 @@ +/* + * Linux ARCnet driver - COM20020 chipset support - function declarations + * + * Written 1997 by David Woodhouse. + * Written 1994-1999 by Avery Pennarun. + * Derived from skeleton.c by Donald Becker. + * + * Special thanks to Contemporary Controls, Inc. (www.ccontrols.com) + * for sponsoring the further development of this driver. + * + * ********************** + * + * The original copyright of skeleton.c was as follows: + * + * skeleton.c Written 1993 by Donald Becker. + * Copyright 1993 United States Government as represented by the + * Director, National Security Agency. This software may only be used + * and distributed according to the terms of the GNU General Public License as + * modified by SRC, incorporated herein by reference. + * + * ********************** + * + * For more details, see drivers/net/arcnet.c + * + * ********************** + */ +#ifndef __COM20020_H +#define __COM20020_H +#include + +int com20020_check(struct net_device *dev); +int com20020_found(struct net_device *dev, int shared); +extern const struct net_device_ops com20020_netdev_ops; + +/* The number of low I/O ports used by the card. */ +#define ARCNET_TOTAL_SIZE 8 + +#define PLX_PCI_MAX_CARDS 2 + +struct ledoffsets { + int green; + int red; +}; + +struct com20020_pci_channel_map { + u32 bar; + u32 offset; + u32 size; /* 0x00 - auto, e.g. length of entire bar */ +}; + +struct com20020_pci_card_info { + const char *name; + u8 devcount; + + struct com20020_pci_channel_map chan_map_tbl[PLX_PCI_MAX_CARDS]; + struct com20020_pci_channel_map misc_map; + + struct ledoffsets leds[PLX_PCI_MAX_CARDS]; + int rotary; + + unsigned int flags; +}; + +struct com20020_priv { + struct com20020_pci_card_info *ci; + struct list_head list_dev; + resource_size_t misc; +}; + +struct com20020_dev { + struct list_head list; + struct net_device *dev; + + struct led_classdev tx_led; + struct led_classdev recon_led; + + struct com20020_priv *pci_priv; + int index; +}; + +#define COM20020_REG_W_INTMASK 0 /* writable */ +#define COM20020_REG_R_STATUS 0 /* readable */ +#define COM20020_REG_W_COMMAND 1 /* standard arcnet commands */ +#define COM20020_REG_R_DIAGSTAT 1 /* diagnostic status */ +#define COM20020_REG_W_ADDR_HI 2 /* control for IO-mapped memory */ +#define COM20020_REG_W_ADDR_LO 3 +#define COM20020_REG_RW_MEMDATA 4 /* data port for IO-mapped memory */ +#define COM20020_REG_W_SUBADR 5 /* the extended port _XREG refers to */ +#define COM20020_REG_W_CONFIG 6 /* configuration */ +#define COM20020_REG_W_XREG 7 /* extra + * (indexed by _CONFIG or _SUBADDR) + */ + +/* in the ADDR_HI register */ +#define RDDATAflag 0x80 /* next access is a read (not a write) */ + +/* in the DIAGSTAT register */ +#define NEWNXTIDflag 0x02 /* ID to which token is passed has changed */ + +/* in the CONFIG register */ +#define RESETcfg 0x80 /* put card in reset state */ +#define TXENcfg 0x20 /* enable TX */ +#define XTOcfg(x) ((x) << 3) /* extended timeout */ + +/* in SETUP register */ +#define PROMISCset 0x10 /* enable RCV_ALL */ +#define P1MODE 0x80 /* enable P1-MODE for Backplane */ +#define SLOWARB 0x01 /* enable Slow Arbitration for >=5Mbps */ + +/* COM2002x */ +#define SUB_TENTATIVE 0 /* tentative node ID */ +#define SUB_NODE 1 /* node ID */ +#define SUB_SETUP1 2 /* various options */ +#define SUB_TEST 3 /* test/diag register */ + +/* COM20022 only */ +#define SUB_SETUP2 4 /* sundry options */ +#define SUB_BUSCTL 5 /* bus control options */ +#define SUB_DMACOUNT 6 /* DMA count options */ + +static inline void com20020_set_subaddress(struct arcnet_local *lp, + int ioaddr, int val) +{ + if (val < 4) { + lp->config = (lp->config & ~0x03) | val; + outb(lp->config, ioaddr + COM20020_REG_W_CONFIG); + } else { + outb(val, ioaddr + COM20020_REG_W_SUBADR); + } +} + +#endif /* __COM20020_H */ -- cgit v1.3.1