From b8fcd0e588fc256bed3d65a4e23017c5582ecf48 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Tue, 30 Jun 2020 13:40:59 +0200 Subject: ACPICA: Preserve memory opregion mappings The ACPICA's strategy with respect to the handling of memory mappings associated with memory operation regions is to avoid mapping the entire region at once which may be problematic at least in principle (for example, it may lead to conflicts with overlapping mappings having different attributes created by drivers). It may also be wasteful, because memory opregions on some systems take up vast chunks of address space while the fields in those regions actually accessed by AML are sparsely distributed. For this reason, a one-page "window" is mapped for a given opregion on the first memory access through it and if that "window" does not cover an address range accessed through that opregion subsequently, it is unmapped and a new "window" is mapped to replace it. Next, if the new "window" is not sufficient to acess memory through the opregion in question in the future, it will be replaced with yet another "window" and so on. That may lead to a suboptimal sequence of memory mapping and unmapping operations, for example if two fields in one opregion separated from each other by a sufficiently wide chunk of unused address space are accessed in an alternating pattern. The situation may still be suboptimal if the deferred unmapping introduced previously is supported by the OS layer. For instance, the alternating memory access pattern mentioned above may produce a relatively long list of mappings to release with substantial duplication among the entries in it, which could be avoided if acpi_ex_system_memory_space_handler() did not release the mapping used by it previously as soon as the current access was not covered by it. In order to improve that, modify acpi_ex_system_memory_space_handler() to preserve all of the memory mappings created by it until the memory regions associated with them go away. Accordingly, update acpi_ev_system_memory_region_setup() to unmap all memory associated with memory opregions that go away. Reported-by: Dan Williams Tested-by: Xiang Li Signed-off-by: Rafael J. Wysocki --- include/acpi/actypes.h | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) (limited to 'include/acpi') diff --git a/include/acpi/actypes.h b/include/acpi/actypes.h index aa236b9e6f24..d005e35ab399 100644 --- a/include/acpi/actypes.h +++ b/include/acpi/actypes.h @@ -1201,12 +1201,18 @@ struct acpi_pci_id { u16 function; }; +struct acpi_mem_mapping { + acpi_physical_address physical_address; + u8 *logical_address; + acpi_size length; + struct acpi_mem_mapping *next_mm; +}; + struct acpi_mem_space_context { u32 length; acpi_physical_address address; - acpi_physical_address mapped_physical_address; - u8 *mapped_logical_address; - acpi_size mapped_length; + struct acpi_mem_mapping *cur_mm; + struct acpi_mem_mapping *first_mm; }; /* -- cgit v1.2.3 From 10cfde5dc695856c4fe93f0679d2fdd8e0d2a147 Mon Sep 17 00:00:00 2001 From: "Gustavo A. R. Silva" Date: Mon, 20 Jul 2020 10:31:19 -0700 Subject: ACPICA: Replace one-element array with flexible-array ACPICA commit 7ba2f3d91a32f104765961fda0ed78b884ae193d The current codebase makes use of one-element arrays in the following form: struct something { int length; u8 data[1]; }; struct something *instance; instance = kmalloc(sizeof(*instance) + size, GFP_KERNEL); instance->length = size; memcpy(instance->data, source, size); but the preferred mechanism to declare variable-length types such as these ones is a flexible array member[1][2], introduced in C99: struct foo { int stuff; struct boo array[]; }; By making use of the mechanism above, we will get a compiler warning in case the flexible array does not occur last in the structure, which will help us prevent some kind of undefined behavior bugs from being inadvertently introduced[3] to the linux codebase from now on. This issue was found with the help of Coccinelle and audited _manually_. [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html [2] https://github.com/KSPP/linux/issues/21 [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Link: https://github.com/acpica/acpica/commit/7ba2f3d9 Signed-off-by: Gustavo A. R. Silva Signed-off-by: Erik Kaneda Signed-off-by: Bob Moore Signed-off-by: Rafael J. Wysocki --- drivers/acpi/acpica/utids.c | 3 +-- include/acpi/actypes.h | 2 +- 2 files changed, 2 insertions(+), 3 deletions(-) (limited to 'include/acpi') diff --git a/drivers/acpi/acpica/utids.c b/drivers/acpi/acpica/utids.c index 3bb06935a2ad..3e68864ef242 100644 --- a/drivers/acpi/acpica/utids.c +++ b/drivers/acpi/acpica/utids.c @@ -263,8 +263,7 @@ acpi_ut_execute_CID(struct acpi_namespace_node *device_node, * 3) Size of the actual CID strings */ cid_list_size = sizeof(struct acpi_pnp_device_id_list) + - ((count - 1) * sizeof(struct acpi_pnp_device_id)) + - string_area_size; + (count * sizeof(struct acpi_pnp_device_id)) + string_area_size; cid_list = ACPI_ALLOCATE_ZEROED(cid_list_size); if (!cid_list) { diff --git a/include/acpi/actypes.h b/include/acpi/actypes.h index aa236b9e6f24..735921c833f8 100644 --- a/include/acpi/actypes.h +++ b/include/acpi/actypes.h @@ -1146,7 +1146,7 @@ struct acpi_pnp_device_id { struct acpi_pnp_device_id_list { u32 count; /* Number of IDs in Ids array */ u32 list_size; /* Size of list, including ID strings */ - struct acpi_pnp_device_id ids[1]; /* ID array */ + struct acpi_pnp_device_id ids[]; /* ID array */ }; /* -- cgit v1.2.3 From 2861ba7a0c6c4ba835347686c19304c32ee15961 Mon Sep 17 00:00:00 2001 From: Bob Moore Date: Mon, 20 Jul 2020 10:31:21 -0700 Subject: ACPICA: Update version to 20200717 ACPICA commit c1adb9a2a775df7a85df0103342ebf090e1b2016 Version 20200717. Link: https://github.com/acpica/acpica/commit/c1adb9a2 Signed-off-by: Bob Moore Signed-off-by: Erik Kaneda Signed-off-by: Rafael J. Wysocki --- include/acpi/acpixf.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/acpi') diff --git a/include/acpi/acpixf.h b/include/acpi/acpixf.h index 459d6981ca96..9dc816641286 100644 --- a/include/acpi/acpixf.h +++ b/include/acpi/acpixf.h @@ -12,7 +12,7 @@ /* Current ACPICA subsystem version in YYYYMMDD format */ -#define ACPI_CA_VERSION 0x20200528 +#define ACPI_CA_VERSION 0x20200717 #include #include -- cgit v1.2.3