Re: [PATCH v3 00/35] acpi: refactor error prone build_header() and packed structures usage in ACPI tables

[Igor Mammedov]

On Tue,  7 Sep 2021 10:47:39 -0400
Igor Mammedov <imammedo@redhat.com> wrote:

Michael,

there are some fixups accumulated (mostly doc/comment related or
dropping some not related code movements),
I can respin series quickly with them incorporated or do fixups on top.
Which one would you prefer?

> v3:
>   1. 
> s/acpi_init_table()|acpi_table_composed()/acpi_table_begin()|acpi_table_end()/
>   2. arm:madt fix incorrect length
>   3. various comment improvments
>   4. rewrite IORT conversion patch due to heavy conflicts with bypass iommu 
> code
>     merged recently
>   5 pick up Eric's Reviewed-By where there wasn't significant change (1)
> 
> v2:
>   - drop test related patches, they will be sent as a separate series
>   - fix bios_loader pointer initialization ordering when using TPM1.2
>   - extend commit message of [1/35] and add extra comment about
>     table length patching 
> 
> Highlights:
>   * drop pointer arithmetic in ACPI tables code
>   * use endian agnostic API
>   * simplifies review of tables. /in most cases just line by line comparision 
> with spec/
> 
> Series replaces build_header() with acpi_table_begin()/acpi_table_end()
> API that hides pointer/offset arithmetic from user, to prevent
> errors caused by it [1].
> While doing above, it was necessary to split table header from
> packed structure that was describing the table, which is
> counter-productive since it still leaves packed structure drawbacks.
> So that sort of forced me to rewrite tables that were composed with
> help of packed structures to preferred build_append_int_noprefix() API.
> In cases where refactoring to build_append_int_noprefix() was small,
> it was squashed with acpi_table_begin()/acpi_table_end() patch.
> Conversion reduced code size quite a bit despite me adding doc comments
> for every table row.
> 
> 1) commits
>    bb9feea43179 x86: acpi: use offset instead of pointer when using 
> build_header()
>    4d027afeb3a9 Virt: ACPI: fix qemu assert due to re-assigned table data 
> address
> 
> Link to repo with this series and tests to validate it:
>    https://gitlab.com/imammedo/qemu/-/commits/acpi_build_header_refactoring_v3
> 
> Previous v2 revision can be found at:
>    https://www.mail-archive.com/qemu-devel@nongnu.org/msg822151.html
> 
> 
> CC: mst@redhat.com
> 
> Igor Mammedov (35):
>   acpi: add helper routines to initialize ACPI tables
>   acpi: build_rsdt: use acpi_table_begin()/acpi_table_end() instead of
>     build_header()
>   acpi: build_xsdt: use acpi_table_begin()/acpi_table_end() instead of
>     build_header()
>   acpi: build_slit: use acpi_table_begin()/acpi_table_end() instead of
>     build_header()
>   acpi: build_fadt: use acpi_table_begin()/acpi_table_end() instead of
>     build_header()
>   acpi: build_tpm2: use acpi_table_begin()/acpi_table_end() instead of
>     build_header()
>   acpi: acpi_build_hest: use acpi_table_begin()/acpi_table_end() instead
>     of build_header()
>   acpi: build_mcfg: use acpi_table_begin()/acpi_table_end() instead of
>     build_header()
>   acpi: build_hmat: use acpi_table_begin()/acpi_table_end() instead of
>     build_header()
>   acpi: nvdimm_build_nfit: use acpi_table_begin()/acpi_table_end()
>     instead of build_header()
>   acpi: nvdimm_build_ssdt: use acpi_table_begin()/acpi_table_end()
>     instead of build_header()
>   acpi: vmgenid_build_acpi: use acpi_table_begin()/acpi_table_end()
>     instead of build_header()
>   acpi: x86: build_dsdt: use acpi_table_begin()/acpi_table_end() instead
>     of build_header()
>   acpi: build_hpet: use acpi_table_begin()/acpi_table_end() instead of
>     build_header()
>   acpi: build_tpm_tcpa: use acpi_table_begin()/acpi_table_end() instead
>     of build_header()
>   acpi: arm/x86: build_srat: use acpi_table_begin()/acpi_table_end()
>     instead of build_header()
>   acpi: use build_append_int_noprefix() API to compose SRAT table
>   acpi: build_dmar_q35: use acpi_table_begin()/acpi_table_end() instead
>     of build_header()
>   acpi: build_waet: use acpi_table_begin()/acpi_table_end() instead of
>     build_header()
>   acpi: build_amd_iommu: use acpi_table_begin()/acpi_table_end() instead
>     of build_header()
>   acpi: madt: arm/x86: use acpi_table_begin()/acpi_table_end() instead
>     of build_header()
>   acpi: x86: remove dead code
>   acpi: x86: set enabled when composing _MAT entries
>   acpi: x86: madt: use build_append_int_noprefix() API to compose MADT
>     table
>   acpi: arm/virt: madt: use build_append_int_noprefix() API to compose
>     MADT table
>   acpi: build_dsdt_microvm: use acpi_table_begin()/acpi_table_end()
>     instead of build_header()
>   acpi: arm: virt: build_dsdt: use acpi_table_begin()/acpi_table_end()
>     instead of build_header()
>   acpi: arm: virt: build_iort: use acpi_table_begin()/acpi_table_end()
>     instead of build_header()
>   acpi: arm/virt: convert build_iort() to endian agnostic
>     build_append_FOO() API
>   acpi: arm/virt: build_spcr: fix invalid cast
>   acpi: arm/virt: build_spcr: use acpi_table_begin()/acpi_table_end()
>     instead of build_header()
>   acpi: arm/virt: build_gtdt: use acpi_table_begin()/acpi_table_end()
>     instead of build_header()
>   acpi: build_facs: use build_append_int_noprefix() API to compose table
>   acpi: remove no longer used build_header()
>   acpi: AcpiGenericAddress no longer used to map/access fields of MMIO,
>     drop packed attribute
> 
>  include/hw/acpi/acpi-defs.h          | 528 +-----------------------
>  include/hw/acpi/acpi_dev_interface.h |   3 +-
>  include/hw/acpi/aml-build.h          |  38 +-
>  include/hw/i386/pc.h                 |   6 +-
>  hw/acpi/acpi-x86-stub.c              |   3 +-
>  hw/acpi/aml-build.c                  | 197 +++++----
>  hw/acpi/cpu.c                        |  17 +-
>  hw/acpi/ghes.c                       |  10 +-
>  hw/acpi/hmat.c                       |  14 +-
>  hw/acpi/nvdimm.c                     |  64 ++-
>  hw/acpi/pci.c                        |  18 +-
>  hw/acpi/vmgenid.c                    |  16 +-
>  hw/arm/virt-acpi-build.c             | 577 +++++++++++++++------------
>  hw/i386/acpi-build.c                 | 304 +++++++-------
>  hw/i386/acpi-common.c                | 158 ++++----
>  hw/i386/acpi-microvm.c               |  13 +-
>  16 files changed, 798 insertions(+), 1168 deletions(-)
>