linux-toradex.git/drivers/acpi/tables.c, branch v6.15-rc7

gcc-15: disable '-Wunterminated-string-initialization' entirely for now

2025-04-20T22:30:53+00:00

I had left the warning around but as a non-fatal error to get my gcc-15
builds going, but fixed up some of the most annoying warning cases so
that it wouldn't be *too* verbose.

Because I like the _concept_ of the warning, even if I detested the
implementation to shut it up.

It turns out the implementation to shut it up is even more broken than I
thought, and my "shut up most of the warnings" patch just caused fatal
errors on gcc-14 instead.

I had tested with clang, but when I upgrade my development environment,
I try to do it on all machines because I hate having different systems
to maintain, and hadn't realized that gcc-14 now had issues.

The ACPI case is literally why I wanted to have a *type* that doesn't
trigger the warning (see commit d5d45a7f2619: "gcc-15: make
'unterminated string initialization' just a warning"), instead of
marking individual places as "__nonstring".

But gcc-14 doesn't like that __nonstring location that shut gcc-15 up,
because it's on an array of char arrays, not on one single array:

  drivers/acpi/tables.c:399:1: error: 'nonstring' attribute ignored on objects of type 'const char[][4]' [-Werror=attributes]
    399 | static const char table_sigs[][ACPI_NAMESEG_SIZE] __initconst __nonstring = {
        | ^~~~~~

and my attempts to nest it properly with a type had failed, because of
how gcc doesn't like marking the types as having attributes, only
symbols.

There may be some trick to it, but I was already annoyed by the bad
attribute design, now I'm just entirely fed up with it.

I wish gcc had a proper way to say "this type is a *byte* array, not a
string".

The obvious thing would be to distinguish between "char []" and an
explicitly signed "unsigned char []" (as opposed to an implicitly
unsigned char, which is typically an architecture-specific default, but
for the kernel is universal thanks to '-funsigned-char').

But any "we can typedef a 8-bit type to not become a string just because
it's an array" model would be fine.

But "__attribute__((nonstring))" is sadly not that sane model.

Reported-by: Chris Clayton 
Fixes: 4b4bd8c50f48 ("gcc-15: acpi: sprinkle random '__nonstring' crumbles around")
Fixes: d5d45a7f2619 ("gcc-15: make 'unterminated string initialization' just a warning")
Signed-off-by: Linus Torvalds

gcc-15: acpi: sprinkle random '__nonstring' crumbles around

2025-04-20T18:57:54+00:00

This is not great: I'd much rather introduce a typedef that is a "ACPI
name byte buffer", and use that to mark these special 4-byte ACPI names
that do not use NUL termination.

But as noted in the previous commit ("gcc-15: make 'unterminated string
initialization' just a warning") gcc doesn't actually seem to support
that notion, so instead you have to just mark every single array
declaration individually.

So this is not pretty, but this gets rid of the bulk of the annoying
warnings during an allmodconfig build for me.

Signed-off-by: Linus Torvalds

ACPI: tables: Use string choice helpers

2025-01-07T18:12:43+00:00

Use str_enabled_disabled string helpers for better readability and to
fix cocci warning.

Reported-by: kernel test robot 
Closes: https://lore.kernel.org/r/202501010947.0e3GVHNa-lkp@intel.com/
Reported-by: Julia Lawall 
Closes: https://lore.kernel.org/r/202501010947.0e3GVHNa-lkp@intel.com/
Signed-off-by: Sunil V L 
Link: https://patch.msgid.link/20250103035122.50315-1-sunilvl@ventanamicro.com
Signed-off-by: Rafael J. Wysocki

ACPI: tables: Print MULTIPROC_WAKEUP when MADT is parsed

2024-06-17T15:46:28+00:00

When MADT is parsed, print MULTIPROC_WAKEUP information:

  ACPI: MP Wakeup (version[1], mailbox[0x7fffd000], reset[0x7fffe068])

This debug information will be very helpful during bringup.

Signed-off-by: Kirill A. Shutemov 
Signed-off-by: Borislav Petkov (AMD) 
Reviewed-by: Baoquan He 
Reviewed-by: Kuppuswamy Sathyanarayanan 
Acked-by: Kai Huang 
Acked-by: Rafael J. Wysocki 
Tested-by: Tao Liu 
Link: https://lore.kernel.org/r/20240614095904.1345461-20-kirill.shutemov@linux.intel.com

lib/firmware_table: Provide buffer length argument to cdat_table_parse()

2024-03-13T07:03:21+00:00

There exist card implementations with a CDAT table using a fixed size
buffer, but with entries filled in that do not fill the whole table
length size. Then, the last entry in the CDAT table may not mark the
end of the CDAT table buffer specified by the length field in the CDAT
header. It can be shorter with trailing unused (zero'ed) data. The
actual table length is determined while reading all CDAT entries of
the table with DOE.

If the table is greater than expected (containing zero'ed trailing
data), the CDAT parser fails with:

 [   48.691717] Malformed DSMAS table length: (24:0)
 [   48.702084] [CDAT:0x00] Invalid zero length
 [   48.711460] cxl_port endpoint1: Failed to parse CDAT: -22

In addition, a check of the table buffer length is missing to prevent
an out-of-bound access then parsing the CDAT table.

Hardening code against device returning borked table. Fix that by
providing an optional buffer length argument to
acpi_parse_entries_array() that can be used by cdat_table_parse() to
propagate the buffer size down to its users to check the buffer
length. This also prevents a possible out-of-bound access mentioned.

Add a check to warn about a malformed CDAT table length.

Cc: Rafael J. Wysocki 
Cc: Len Brown 
Reviewed-by: Dave Jiang 
Signed-off-by: Robert Richter 
Reviewed-by: Jonathan Cameron 
Link: https://lore.kernel.org/r/ZdEnopFO0Tl3t2O1@rric.localdomain
Signed-off-by: Dan Williams

lib/firmware_table: tables: Add CDAT table parsing support

2023-12-22T22:23:13+00:00

The CDAT table is very similar to ACPI tables when it comes to sub-table
and entry structures. The helper functions can be also used to parse the
CDAT table. Add support to the helper functions to deal with an external
CDAT table, and also handle the endieness since CDAT can be processed by a
BE host. Export a function cdat_table_parse() for CXL driver to parse
a CDAT table.

In order to minimize ACPICA code changes, __force is being utilized to deal
with the case of a big endian (BE) host parsing a CDAT. All CDAT data
structure variables are being force casted to __leX as appropriate.

Cc: Rafael J. Wysocki 
Cc: Len Brown 
Reviewed-by: Jonathan Cameron 
Signed-off-by: Dave Jiang 
Acked-by: Rafael J. Wysocki 
Link: https://lore.kernel.org/r/170319615131.2212653.10932785667981494238.stgit@djiang5-mobl3
Signed-off-by: Dan Williams

acpi: Move common tables helper functions to common lib

2023-10-28T03:48:03+00:00

Some of the routines in ACPI driver/acpi/tables.c can be shared with
parsing CDAT. CDAT is a device-provided data structure that is formatted
similar to a platform provided ACPI table. CDAT is used by CXL and can
exist on platforms that do not use ACPI. Split out the common routine
from ACPI to accommodate platforms that do not support ACPI and move that
to /lib. The common routines can be built outside of ACPI if
FIRMWARE_TABLES is selected.

Link: https://lore.kernel.org/linux-cxl/CAJZ5v0jipbtTNnsA0-o5ozOk8ZgWnOg34m34a9pPenTyRLj=6A@mail.gmail.com/
Suggested-by: "Rafael J. Wysocki" 
Reviewed-by: Hanjun Guo 
Reviewed-by: Jonathan Cameron 
Signed-off-by: Dave Jiang 
Acked-by: "Rafael J. Wysocki" 
Link: https://lore.kernel.org/r/169713683430.2205276.17899451119920103445.stgit@djiang5-mobl3
Signed-off-by: Dan Williams

ACPI: tables: Print RINTC information when MADT is parsed

2023-06-01T15:44:59+00:00

When MADT is parsed, print RINTC information as below:

ACPI: RISC-V INTC (acpi_uid[0x0000] hart_id[0x0] enabled)
ACPI: RISC-V INTC (acpi_uid[0x0001] hart_id[0x1] enabled)
...
ACPI: RISC-V INTC (acpi_uid[0x000f] hart_id[0xf] enabled)

This debug information will be very helpful during bring up.

Signed-off-by: Sunil V L 
Acked-by: Rafael J. Wysocki 
Reviewed-by: Andrew Jones 
Link: https://lore.kernel.org/r/20230515054928.2079268-5-sunilvl@ventanamicro.com
Signed-off-by: Palmer Dabbelt

ACPI: tables: Add support for NBFT

2022-12-30T17:39:09+00:00

Add support for the NVMe Boot Firmware Table (NBFT) to facilitate
booting from NVM Express namespaces which are accessed via
NVMe over Fabrics (NVMe-oF).

Signed-off-by: Stuart Hayes 
Reviewed-by: John Meneghini 
Signed-off-by: Rafael J. Wysocki

ACPI: tables: Fix the stale comments for acpi_locate_initial_tables()

2022-11-10T19:15:55+00:00

sdt_entry[] is long gone by commit ceb6c4683902 ("ACPICA: Remove
duplicate table manager"), update the comments to avoid confusion.

Signed-off-by: Hanjun Guo 
Signed-off-by: Rafael J. Wysocki