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/clocksource/timer-goldfish.c | 153 +++++++++++++++++++++++++++++++++++ 1 file changed, 153 insertions(+) create mode 100644 drivers/clocksource/timer-goldfish.c (limited to 'drivers/clocksource/timer-goldfish.c') diff --git a/drivers/clocksource/timer-goldfish.c b/drivers/clocksource/timer-goldfish.c new file mode 100644 index 000000000..3fe12c7ee --- /dev/null +++ b/drivers/clocksource/timer-goldfish.c @@ -0,0 +1,153 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include +#include +#include +#include +#include +#include +#include +#include + +struct goldfish_timer { + struct clocksource cs; + struct clock_event_device ced; + struct resource res; + void __iomem *base; +}; + +static struct goldfish_timer *ced_to_gf(struct clock_event_device *ced) +{ + return container_of(ced, struct goldfish_timer, ced); +} + +static struct goldfish_timer *cs_to_gf(struct clocksource *cs) +{ + return container_of(cs, struct goldfish_timer, cs); +} + +static u64 goldfish_timer_read(struct clocksource *cs) +{ + struct goldfish_timer *timerdrv = cs_to_gf(cs); + void __iomem *base = timerdrv->base; + u32 time_low, time_high; + u64 ticks; + + /* + * time_low: get low bits of current time and update time_high + * time_high: get high bits of time at last time_low read + */ + time_low = gf_ioread32(base + TIMER_TIME_LOW); + time_high = gf_ioread32(base + TIMER_TIME_HIGH); + + ticks = ((u64)time_high << 32) | time_low; + + return ticks; +} + +static int goldfish_timer_set_oneshot(struct clock_event_device *evt) +{ + struct goldfish_timer *timerdrv = ced_to_gf(evt); + void __iomem *base = timerdrv->base; + + gf_iowrite32(0, base + TIMER_ALARM_HIGH); + gf_iowrite32(0, base + TIMER_ALARM_LOW); + gf_iowrite32(1, base + TIMER_IRQ_ENABLED); + + return 0; +} + +static int goldfish_timer_shutdown(struct clock_event_device *evt) +{ + struct goldfish_timer *timerdrv = ced_to_gf(evt); + void __iomem *base = timerdrv->base; + + gf_iowrite32(0, base + TIMER_IRQ_ENABLED); + + return 0; +} + +static int goldfish_timer_next_event(unsigned long delta, + struct clock_event_device *evt) +{ + struct goldfish_timer *timerdrv = ced_to_gf(evt); + void __iomem *base = timerdrv->base; + u64 now; + + now = goldfish_timer_read(&timerdrv->cs); + + now += delta; + + gf_iowrite32(upper_32_bits(now), base + TIMER_ALARM_HIGH); + gf_iowrite32(lower_32_bits(now), base + TIMER_ALARM_LOW); + + return 0; +} + +static irqreturn_t goldfish_timer_irq(int irq, void *dev_id) +{ + struct goldfish_timer *timerdrv = dev_id; + struct clock_event_device *evt = &timerdrv->ced; + void __iomem *base = timerdrv->base; + + gf_iowrite32(1, base + TIMER_CLEAR_INTERRUPT); + + evt->event_handler(evt); + + return IRQ_HANDLED; +} + +int __init goldfish_timer_init(int irq, void __iomem *base) +{ + struct goldfish_timer *timerdrv; + int ret; + + timerdrv = kzalloc_obj(*timerdrv); + if (!timerdrv) + return -ENOMEM; + + timerdrv->base = base; + + timerdrv->ced = (struct clock_event_device){ + .name = "goldfish_timer", + .features = CLOCK_EVT_FEAT_ONESHOT, + .set_state_shutdown = goldfish_timer_shutdown, + .set_state_oneshot = goldfish_timer_set_oneshot, + .set_next_event = goldfish_timer_next_event, + }; + + timerdrv->res = (struct resource){ + .name = "goldfish_timer", + .start = (unsigned long)base, + .end = (unsigned long)base + 0xfff, + }; + + ret = request_resource(&iomem_resource, &timerdrv->res); + if (ret) { + pr_err("Cannot allocate '%s' resource\n", timerdrv->res.name); + return ret; + } + + timerdrv->cs = (struct clocksource){ + .name = "goldfish_timer", + .rating = 400, + .read = goldfish_timer_read, + .mask = CLOCKSOURCE_MASK(64), + .flags = 0, + .max_idle_ns = LONG_MAX, + }; + + clocksource_register_hz(&timerdrv->cs, NSEC_PER_SEC); + + ret = request_irq(irq, goldfish_timer_irq, IRQF_TIMER, + "goldfish_timer", timerdrv); + if (ret) { + pr_err("Couldn't register goldfish-timer interrupt\n"); + return ret; + } + + clockevents_config_and_register(&timerdrv->ced, NSEC_PER_SEC, + 1, 0xffffffff); + + return 0; +} -- cgit v1.3.1