https://github.com/torvalds/linux
Revision 2bbb5fa37475d7aa5fa62f34db1623f3da2dfdfa authored by Hans de Goede on 19 November 2018, 18:06:01 UTC, committed by Rafael J. Wysocki on 21 November 2018, 12:30:13 UTC
Many HP AMD based laptops contain an SMB0001 device like this:

Device (SMBD)
{
    Name (_HID, "SMB0001")  // _HID: Hardware ID
    Name (_CRS, ResourceTemplate ()  // _CRS: Current Resource Settings
    {
        IO (Decode16,
            0x0B20,             // Range Minimum
            0x0B20,             // Range Maximum
            0x20,               // Alignment
            0x20,               // Length
            )
        IRQ (Level, ActiveLow, Shared, )
            {7}
    })
}

The legacy style IRQ resource here causes acpi_dev_get_irqresource() to
be called with legacy=true and this message to show in dmesg:
ACPI: IRQ 7 override to edge, high

This causes issues when later on the AMD0030 GPIO device gets enumerated:

Device (GPIO)
{
    Name (_HID, "AMDI0030")  // _HID: Hardware ID
    Name (_CID, "AMDI0030")  // _CID: Compatible ID
    Name (_UID, Zero)  // _UID: Unique ID
    Method (_CRS, 0, NotSerialized)  // _CRS: Current Resource Settings
    {
	Name (RBUF, ResourceTemplate ()
	{
	    Interrupt (ResourceConsumer, Level, ActiveLow, Shared, ,, )
	    {
		0x00000007,
	    }
	    Memory32Fixed (ReadWrite,
		0xFED81500,         // Address Base
		0x00000400,         // Address Length
		)
	})
	Return (RBUF) /* \_SB_.GPIO._CRS.RBUF */
    }
}

Now acpi_dev_get_irqresource() gets called with legacy=false, but because
of the earlier override of the trigger-type acpi_register_gsi() returns
-EBUSY (because we try to register the same interrupt with a different
trigger-type) and we end up setting IORESOURCE_DISABLED in the flags.

The setting of IORESOURCE_DISABLED causes platform_get_irq() to call
acpi_irq_get() which is not implemented on x86 and returns -EINVAL.
resulting in the following in dmesg:

amd_gpio AMDI0030:00: Failed to get gpio IRQ: -22
amd_gpio: probe of AMDI0030:00 failed with error -22

The SMB0001 is a "virtual" device in the sense that the only way the OS
interacts with it is through calling a couple of methods to do SMBus
transfers. As such it is weird that it has IO and IRQ resources at all,
because the driver for it is not expected to ever access the hardware
directly.

The Linux driver for the SMB0001 device directly binds to the acpi_device
through the acpi_bus, so we do not need to instantiate a platform_device
for this ACPI device. This commit adds the SMB0001 HID to the
forbidden_id_list, avoiding the instantiating of a platform_device for it.
Not instantiating a platform_device means we will no longer call
acpi_dev_get_irqresource() for the legacy IRQ resource fixing the probe of
the AMDI0030 device failing.

BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1644013
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=198715
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=199523
Reported-by: Lukas Kahnert <openproggerfreak@gmail.com>
Tested-by: Marc <suaefar@googlemail.com>
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
1 parent 9ff0119
Raw File
Tip revision: 2bbb5fa37475d7aa5fa62f34db1623f3da2dfdfa authored by Hans de Goede on 19 November 2018, 18:06:01 UTC
ACPI / platform: Add SMB0001 HID to forbidden_id_list
Tip revision: 2bbb5fa
page_poison.c
// SPDX-License-Identifier: GPL-2.0
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/highmem.h>
#include <linux/page_ext.h>
#include <linux/poison.h>
#include <linux/ratelimit.h>

static bool want_page_poisoning __read_mostly;

static int __init early_page_poison_param(char *buf)
{
	if (!buf)
		return -EINVAL;
	return strtobool(buf, &want_page_poisoning);
}
early_param("page_poison", early_page_poison_param);

/**
 * page_poisoning_enabled - check if page poisoning is enabled
 *
 * Return true if page poisoning is enabled, or false if not.
 */
bool page_poisoning_enabled(void)
{
	/*
	 * Assumes that debug_pagealloc_enabled is set before
	 * memblock_free_all.
	 * Page poisoning is debug page alloc for some arches. If
	 * either of those options are enabled, enable poisoning.
	 */
	return (want_page_poisoning ||
		(!IS_ENABLED(CONFIG_ARCH_SUPPORTS_DEBUG_PAGEALLOC) &&
		debug_pagealloc_enabled()));
}
EXPORT_SYMBOL_GPL(page_poisoning_enabled);

static void poison_page(struct page *page)
{
	void *addr = kmap_atomic(page);

	memset(addr, PAGE_POISON, PAGE_SIZE);
	kunmap_atomic(addr);
}

static void poison_pages(struct page *page, int n)
{
	int i;

	for (i = 0; i < n; i++)
		poison_page(page + i);
}

static bool single_bit_flip(unsigned char a, unsigned char b)
{
	unsigned char error = a ^ b;

	return error && !(error & (error - 1));
}

static void check_poison_mem(unsigned char *mem, size_t bytes)
{
	static DEFINE_RATELIMIT_STATE(ratelimit, 5 * HZ, 10);
	unsigned char *start;
	unsigned char *end;

	if (IS_ENABLED(CONFIG_PAGE_POISONING_NO_SANITY))
		return;

	start = memchr_inv(mem, PAGE_POISON, bytes);
	if (!start)
		return;

	for (end = mem + bytes - 1; end > start; end--) {
		if (*end != PAGE_POISON)
			break;
	}

	if (!__ratelimit(&ratelimit))
		return;
	else if (start == end && single_bit_flip(*start, PAGE_POISON))
		pr_err("pagealloc: single bit error\n");
	else
		pr_err("pagealloc: memory corruption\n");

	print_hex_dump(KERN_ERR, "", DUMP_PREFIX_ADDRESS, 16, 1, start,
			end - start + 1, 1);
	dump_stack();
}

static void unpoison_page(struct page *page)
{
	void *addr;

	addr = kmap_atomic(page);
	/*
	 * Page poisoning when enabled poisons each and every page
	 * that is freed to buddy. Thus no extra check is done to
	 * see if a page was posioned.
	 */
	check_poison_mem(addr, PAGE_SIZE);
	kunmap_atomic(addr);
}

static void unpoison_pages(struct page *page, int n)
{
	int i;

	for (i = 0; i < n; i++)
		unpoison_page(page + i);
}

void kernel_poison_pages(struct page *page, int numpages, int enable)
{
	if (!page_poisoning_enabled())
		return;

	if (enable)
		unpoison_pages(page, numpages);
	else
		poison_pages(page, numpages);
}

#ifndef CONFIG_ARCH_SUPPORTS_DEBUG_PAGEALLOC
void __kernel_map_pages(struct page *page, int numpages, int enable)
{
	/* This function does nothing, all work is done via poison pages */
}
#endif
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