From 71b57aca295d61276a60e131d8f62b0cc7cf1a35 Mon Sep 17 00:00:00 2001 From: Xu Rao Date: Tue, 16 Jun 2026 17:36:21 +0800 Subject: [PATCH] ACPI: IPMI: Fix inverted interface check in ipmi_bmc_gone() Before commit a1a69b297e47 ("ACPI / IPMI: Fix race caused by the unprotected ACPI IPMI user"), ipmi_bmc_gone() skipped entries whose interface number did not match the SMI being removed, then killed the matching entry: if (ipmi_device->ipmi_ifnum != iface) continue; __ipmi_dev_kill(ipmi_device); That commit folded the removal block into the existing non-match test while converting the object lifetime handling, but left the comparison unchanged. The old != meant "continue past this entry"; after the refactor it meant "kill this entry". As a result, a single ACPI IPMI interface is never removed when its SMI disappears. If multiple interfaces are tracked, the first interface whose number differs from iface is removed instead, while the interface that actually disappeared remains on driver_data.ipmi_devices. The stale entry is not marked dead and can continue to be selected for ACPI IPMI transactions. It can also prevent the same ACPI handle from being registered again. Change the comparison to == so ipmi_bmc_gone() removes exactly the interface reported as gone by the SMI watcher. This restores the pre-a1a69b297e47 behavior and is the correct interface matching logic. Fixes: a1a69b297e47 ("ACPI / IPMI: Fix race caused by the unprotected ACPI IPMI user") Signed-off-by: Xu Rao Link: https://patch.msgid.link/B486593E06E6F6E0+20260616093621.1039943-1-raoxu@uniontech.com Signed-off-by: Rafael J. Wysocki --- drivers/acpi/acpi_ipmi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/acpi/acpi_ipmi.c b/drivers/acpi/acpi_ipmi.c index 79ce6e72bf29..2dbed92d54b3 100644 --- a/drivers/acpi/acpi_ipmi.c +++ b/drivers/acpi/acpi_ipmi.c @@ -490,7 +490,7 @@ static void ipmi_bmc_gone(int iface) mutex_lock(&driver_data.ipmi_lock); list_for_each_entry_safe(iter, temp, &driver_data.ipmi_devices, head) { - if (iter->ipmi_ifnum != iface) { + if (iter->ipmi_ifnum == iface) { ipmi_device = iter; __ipmi_dev_kill(iter); break;