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 --- samples/watchdog/.gitignore | 2 ++ samples/watchdog/Makefile | 2 ++ samples/watchdog/watchdog-simple.c | 25 +++++++++++++++++++++++++ 3 files changed, 29 insertions(+) create mode 100644 samples/watchdog/.gitignore create mode 100644 samples/watchdog/Makefile create mode 100644 samples/watchdog/watchdog-simple.c (limited to 'samples/watchdog') diff --git a/samples/watchdog/.gitignore b/samples/watchdog/.gitignore new file mode 100644 index 000000000..a70a0150e --- /dev/null +++ b/samples/watchdog/.gitignore @@ -0,0 +1,2 @@ +# SPDX-License-Identifier: GPL-2.0-only +/watchdog-simple diff --git a/samples/watchdog/Makefile b/samples/watchdog/Makefile new file mode 100644 index 000000000..ab39d23dc --- /dev/null +++ b/samples/watchdog/Makefile @@ -0,0 +1,2 @@ +# SPDX-License-Identifier: GPL-2.0 +userprogs-always-y += watchdog-simple diff --git a/samples/watchdog/watchdog-simple.c b/samples/watchdog/watchdog-simple.c new file mode 100644 index 000000000..9ce66d2ca --- /dev/null +++ b/samples/watchdog/watchdog-simple.c @@ -0,0 +1,25 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include +#include + +int main(void) +{ + int fd = open("/dev/watchdog", O_WRONLY); + int ret = 0; + if (fd == -1) { + perror("watchdog"); + exit(EXIT_FAILURE); + } + while (1) { + ret = write(fd, "\0", 1); + if (ret != 1) { + ret = -1; + break; + } + sleep(10); + } + close(fd); + return ret; +} -- cgit v1.3.1