From 7f7b4236f2040d19df1ddaf30047128b41e78de7 Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Fri, 17 Dec 2021 15:13:48 +0100 Subject: [PATCH 1/4] x86/PCI: Ignore E820 reservations for bridge windows on newer systems Some BIOS-es contain a bug where they add addresses which map to system RAM in the PCI host bridge window returned by the ACPI _CRS method, see commit 4dc2287c1805 ("x86: avoid E820 regions when allocating address space"). To work around this bug Linux excludes E820 reserved addresses when allocating addresses from the PCI host bridge window since 2010. Recently (2019) some systems have shown-up with E820 reservations which cover the entire _CRS returned PCI bridge memory window, causing all attempts to assign memory to PCI BARs which have not been setup by the BIOS to fail. For example here are the relevant dmesg bits from a Lenovo IdeaPad 3 15IIL 81WE: [mem 0x000000004bc50000-0x00000000cfffffff] reserved pci_bus 0000:00: root bus resource [mem 0x65400000-0xbfffffff window] The ACPI specifications appear to allow this new behavior: The relationship between E820 and ACPI _CRS is not really very clear. ACPI v6.3, sec 15, table 15-374, says AddressRangeReserved means: This range of addresses is in use or reserved by the system and is not to be included in the allocatable memory pool of the operating system's memory manager. and it may be used when: The address range is in use by a memory-mapped system device. Furthermore, sec 15.2 says: Address ranges defined for baseboard memory-mapped I/O devices, such as APICs, are returned as reserved. A PCI host bridge qualifies as a baseboard memory-mapped I/O device, and its apertures are in use and certainly should not be included in the general allocatable pool, so the fact that some BIOS-es reports the PCI aperture as "reserved" in E820 doesn't seem like a BIOS bug. So it seems that the excluding of E820 reserved addresses is a mistake. Ideally Linux would fully stop excluding E820 reserved addresses, but then the old systems this was added for will regress. Instead keep the old behavior for old systems, while ignoring the E820 reservations for any systems from now on. Old systems are defined here as BIOS year < 2018, this was chosen to make sure that E820 reservations will not be used on the currently affected systems, while at the same time also taking into account that the systems for which the E820 checking was originally added may have received BIOS updates for quite a while (esp. CVE related ones), giving them a more recent BIOS year then 2010. BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=206459 BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1868899 BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1871793 BugLink: https://bugs.launchpad.net/bugs/1878279 BugLink: https://bugs.launchpad.net/bugs/1931715 BugLink: https://bugs.launchpad.net/bugs/1932069 BugLink: https://bugs.launchpad.net/bugs/1921649 Reviewed-by: Mika Westerberg Acked-by: Bjorn Helgaas Signed-off-by: Hans de Goede Signed-off-by: Rafael J. Wysocki --- arch/x86/kernel/resource.c | 23 ++++++++++++++++++++++- 1 file changed, 22 insertions(+), 1 deletion(-) diff --git a/arch/x86/kernel/resource.c b/arch/x86/kernel/resource.c index 9b9fb7882c20..9ae64f9af956 100644 --- a/arch/x86/kernel/resource.c +++ b/arch/x86/kernel/resource.c @@ -1,4 +1,5 @@ // SPDX-License-Identifier: GPL-2.0 +#include #include #include @@ -23,11 +24,31 @@ static void resource_clip(struct resource *res, resource_size_t start, res->start = end + 1; } +/* + * Some BIOS-es contain a bug where they add addresses which map to + * system RAM in the PCI host bridge window returned by the ACPI _CRS + * method, see commit 4dc2287c1805 ("x86: avoid E820 regions when + * allocating address space"). To avoid this Linux by default excludes + * E820 reservations when allocating addresses since 2010. + * In 2019 some systems have shown-up with E820 reservations which cover + * the entire _CRS returned PCI host bridge window, causing all attempts + * to assign memory to PCI BARs to fail if Linux uses E820 reservations. + * + * Ideally Linux would fully stop using E820 reservations, but then + * the old systems this was added for will regress. + * Instead keep the old behavior for old systems, while ignoring the + * E820 reservations for any systems from now on. + */ static void remove_e820_regions(struct resource *avail) { - int i; + int i, year = dmi_get_bios_year(); struct e820_entry *entry; + if (year >= 2018) + return; + + pr_info_once("PCI: Removing E820 reservations from host bridge windows\n"); + for (i = 0; i < e820_table->nr_entries; i++) { entry = &e820_table->entries[i]; From 2cea3ec5b0099d0e9dd6752aa86e08bce38d6b32 Mon Sep 17 00:00:00 2001 From: Jiasheng Jiang Date: Fri, 7 Jan 2022 11:35:16 +0800 Subject: [PATCH 2/4] ACPI: APD: Check for NULL pointer after calling devm_ioremap() Because devres_alloc() may fail, devm_ioremap() may return NULL. Then, 'clk_data->base' will be assigned to clkdev->data->base in platform_device_register_data(). The PTR_ERR_OR_ZERO() check on clk_data does not cover 'base', so it is better to add an explicit check against NULL after updating it. Fixes: 3f4ba94e3615 ("ACPI: APD: Add AMD misc clock handler support") Signed-off-by: Jiasheng Jiang [ rjw: Changelog rewrite ] Signed-off-by: Rafael J. Wysocki --- drivers/acpi/acpi_apd.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/acpi/acpi_apd.c b/drivers/acpi/acpi_apd.c index 6e02448d15d9..9db6409ecb47 100644 --- a/drivers/acpi/acpi_apd.c +++ b/drivers/acpi/acpi_apd.c @@ -95,6 +95,8 @@ static int fch_misc_setup(struct apd_private_data *pdata) resource_size(rentry->res)); break; } + if (!clk_data->base) + return -ENOMEM; acpi_dev_free_resource_list(&resource_list); From ee3fe99ff0a27108ac38d9766ac0e92f5ec35692 Mon Sep 17 00:00:00 2001 From: Mark Langsdorf Date: Wed, 5 Jan 2022 11:47:14 -0600 Subject: [PATCH 3/4] ACPI: SPCR: check if table->serial_port.access_width is too wide If table->serial_port.access_width is more than 29, it causes undefined behavior when ACPI_ACCESS_BIT_WIDTH shifts it to (1 << ((size) + 2)): [ 0.000000] UBSAN: Undefined behaviour in drivers/acpi/spcr.c:114:11 [ 0.000000] shift exponent 102 is too large for 32-bit type 'int' Use the new ACPI_ACCESS_ defines to test that serial_port.access_width is less than 30 and set it to 6 if it is not. Signed-off-by: Mark Langsdorf Signed-off-by: Rafael J. Wysocki --- drivers/acpi/spcr.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/drivers/acpi/spcr.c b/drivers/acpi/spcr.c index 25c2d0be953e..d589543875b8 100644 --- a/drivers/acpi/spcr.c +++ b/drivers/acpi/spcr.c @@ -107,8 +107,13 @@ int __init acpi_parse_spcr(bool enable_earlycon, bool enable_console) pr_info("SPCR table version %d\n", table->header.revision); if (table->serial_port.space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY) { - switch (ACPI_ACCESS_BIT_WIDTH(( - table->serial_port.access_width))) { + u32 bit_width = table->serial_port.access_width; + + if (bit_width > ACPI_ACCESS_BIT_MAX) { + pr_err("Unacceptable wide SPCR Access Width. Defaulting to byte size\n"); + bit_width = ACPI_ACCESS_BIT_DEFAULT; + } + switch (ACPI_ACCESS_BIT_WIDTH((bit_width))) { default: pr_err("Unexpected SPCR Access Width. Defaulting to byte size\n"); fallthrough; From 415b4b6c447ae03cb1d9cfc91df39616c92f15e2 Mon Sep 17 00:00:00 2001 From: kernel test robot Date: Thu, 6 Jan 2022 01:45:56 +0800 Subject: [PATCH 4/4] ACPI: PCC: pcc_ctx can be static drivers/acpi/acpi_pcc.c:34:22: warning: symbol 'pcc_ctx' was not declared. Should it be static? Reported-by: kernel test robot Signed-off-by: kernel test robot Reviewed-by: Sudeep Holla Signed-off-by: Rafael J. Wysocki --- drivers/acpi/acpi_pcc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/acpi/acpi_pcc.c b/drivers/acpi/acpi_pcc.c index 41e3ebd204ff..a12b55d81209 100644 --- a/drivers/acpi/acpi_pcc.c +++ b/drivers/acpi/acpi_pcc.c @@ -31,7 +31,7 @@ struct pcc_data { struct acpi_pcc_info ctx; }; -struct acpi_pcc_info pcc_ctx; +static struct acpi_pcc_info pcc_ctx; static void pcc_rx_callback(struct mbox_client *cl, void *m) {