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/dma/dw/internal.h | 101 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 101 insertions(+) create mode 100644 drivers/dma/dw/internal.h (limited to 'drivers/dma/dw/internal.h') diff --git a/drivers/dma/dw/internal.h b/drivers/dma/dw/internal.h new file mode 100644 index 000000000..f1bd06a20 --- /dev/null +++ b/drivers/dma/dw/internal.h @@ -0,0 +1,101 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Driver for the Synopsys DesignWare DMA Controller + * + * Copyright (C) 2013 Intel Corporation + */ + +#ifndef _DMA_DW_INTERNAL_H +#define _DMA_DW_INTERNAL_H + +#include + +#include "regs.h" + +int do_dma_probe(struct dw_dma_chip *chip); +int do_dma_remove(struct dw_dma_chip *chip); + +void do_dw_dma_on(struct dw_dma *dw); +void do_dw_dma_off(struct dw_dma *dw); + +int do_dw_dma_disable(struct dw_dma_chip *chip); +int do_dw_dma_enable(struct dw_dma_chip *chip); + +extern bool dw_dma_filter(struct dma_chan *chan, void *param); + +#ifdef CONFIG_ACPI +void dw_dma_acpi_controller_register(struct dw_dma *dw); +void dw_dma_acpi_controller_free(struct dw_dma *dw); +#else /* !CONFIG_ACPI */ +static inline void dw_dma_acpi_controller_register(struct dw_dma *dw) {} +static inline void dw_dma_acpi_controller_free(struct dw_dma *dw) {} +#endif /* !CONFIG_ACPI */ + +struct platform_device; + +#ifdef CONFIG_OF +struct dw_dma_platform_data *dw_dma_parse_dt(struct platform_device *pdev); +void dw_dma_of_controller_register(struct dw_dma *dw); +void dw_dma_of_controller_free(struct dw_dma *dw); +#else +static inline struct dw_dma_platform_data *dw_dma_parse_dt(struct platform_device *pdev) +{ + return NULL; +} +static inline void dw_dma_of_controller_register(struct dw_dma *dw) {} +static inline void dw_dma_of_controller_free(struct dw_dma *dw) {} +#endif + +struct dw_dma_chip_pdata { + const struct dw_dma_platform_data *pdata; + int (*probe)(struct dw_dma_chip *chip); + int (*remove)(struct dw_dma_chip *chip); + struct dw_dma_chip *chip; + u8 m_master; + u8 p_master; +}; + +static __maybe_unused const struct dw_dma_chip_pdata dw_dma_chip_pdata = { + .probe = dw_dma_probe, + .remove = dw_dma_remove, + .m_master = 0, + .p_master = 1, +}; + +static const struct dw_dma_platform_data idma32_pdata = { + .nr_channels = 8, + .chan_allocation_order = CHAN_ALLOCATION_ASCENDING, + .chan_priority = CHAN_PRIORITY_ASCENDING, + .block_size = 131071, + .nr_masters = 1, + .data_width = {4}, + .multi_block = {1, 1, 1, 1, 1, 1, 1, 1}, +}; + +static __maybe_unused const struct dw_dma_chip_pdata idma32_chip_pdata = { + .pdata = &idma32_pdata, + .probe = idma32_dma_probe, + .remove = idma32_dma_remove, + .m_master = 0, + .p_master = 0, +}; + +static const struct dw_dma_platform_data xbar_pdata = { + .nr_channels = 8, + .chan_allocation_order = CHAN_ALLOCATION_ASCENDING, + .chan_priority = CHAN_PRIORITY_ASCENDING, + .block_size = 131071, + .nr_masters = 1, + .data_width = {4}, + .quirks = DW_DMA_QUIRK_XBAR_PRESENT, +}; + +static __maybe_unused const struct dw_dma_chip_pdata xbar_chip_pdata = { + .pdata = &xbar_pdata, + .probe = idma32_dma_probe, + .remove = idma32_dma_remove, + .m_master = 0, + .p_master = 0, +}; + +#endif /* _DMA_DW_INTERNAL_H */ -- cgit v1.3.1