Re: [PATCH for-6.0] x86: acpi: use offset instead of pointer when using build_header()

["Michael S. Tsirkin" <mst@redhat.com>]

On Tue, Apr 13, 2021 at 03:18:16PM +0200, Igor Mammedov wrote:
> On Tue, 13 Apr 2021 08:14:56 -0400
> "Michael S. Tsirkin" <mst@redhat.com> wrote:
> 
> > On Tue, Apr 13, 2021 at 07:14:00AM -0400, Igor Mammedov wrote:
> > > Do the same as in commit
> > >  (4d027afeb3a97 Virt: ACPI: fix qemu assert due to re-assigned table data address)

Format:

commit 4d027afeb3a97 ("Virt: ACPI: fix qemu assert due to re-assigned table data address")

> > > for remaining tables that happen to use saved at
> > > the beginning pointer to build header to avoid assert
> > > when table_data is relocated due to implicit re-size.
> > > 
> > > Reported-in: https://bugs.launchpad.net/bugs/1923497  
> > 
> > Doesn't this fix the bug? If so -
> > Isn't this Fixes: ?
> that's buried in history
> 
> Fixes: 243bdb79fb0b2ed hw/arm/virt-acpi-build: Generate RSDT table
> Fixes: cb51ac2ffe3649e hw/arm/virt: generate 64-bit addressable ACPI objects
> Fixes: 4338416064303aa acpi: Move build_tpm2() in the generic part
> Fixes: 72c194f7e75cb64 i386: ACPI table generation code from seabios
> Fixes: 711b20b479aa96e Add ACPI tables for TPM


I just mean:

    Buglink: https://bugs.launchpad.net/qemu/+bug/1921138

as opposed to Reported.

Also do we CC stable for this?

>  
> > > Signed-off-by: Igor Mammedov <imammedo@redhat.com>


patch itself ok:

Acked-by: Michael S. Tsirkin <mst@redhat.com>

> > > ---
> > > PS:
> > >  I have build_header() refactoring patch that requires offset
> > >  instead of pointer, to make it harder to misuse but it's
> > >  a bit intrusive for last minute fixes. So here goes simplified
> > >  variant, and I'll post refactoring patch for 6.1. later.
> > > ---
> > >  hw/acpi/aml-build.c  | 15 +++++++++------
> > >  hw/i386/acpi-build.c |  8 ++++++--
> > >  2 files changed, 15 insertions(+), 8 deletions(-)
> > > 
> > > diff --git a/hw/acpi/aml-build.c b/hw/acpi/aml-build.c
> > > index d33ce8954a..f0035d2b4a 100644
> > > --- a/hw/acpi/aml-build.c
> > > +++ b/hw/acpi/aml-build.c
> > > @@ -1830,6 +1830,7 @@ build_rsdt(GArray *table_data, BIOSLinker *linker, GArray *table_offsets,
> > >      int i;
> > >      unsigned rsdt_entries_offset;
> > >      AcpiRsdtDescriptorRev1 *rsdt;
> > > +    int rsdt_start = table_data->len;
> > >      const unsigned table_data_len = (sizeof(uint32_t) * table_offsets->len);
> > >      const unsigned rsdt_entry_size = sizeof(rsdt->table_offset_entry[0]);
> > >      const size_t rsdt_len = sizeof(*rsdt) + table_data_len;
> > > @@ -1846,7 +1847,8 @@ build_rsdt(GArray *table_data, BIOSLinker *linker, GArray *table_offsets,
> > >              ACPI_BUILD_TABLE_FILE, ref_tbl_offset);
> > >      }
> > >      build_header(linker, table_data,
> > > -                 (void *)rsdt, "RSDT", rsdt_len, 1, oem_id, oem_table_id);
> > > +                 (void *)(table_data->data + rsdt_start),
> > > +                 "RSDT", rsdt_len, 1, oem_id, oem_table_id);
> > >  }
> > >  
> > >  /* Build xsdt table */
> > > @@ -1857,6 +1859,7 @@ build_xsdt(GArray *table_data, BIOSLinker *linker, GArray *table_offsets,
> > >      int i;
> > >      unsigned xsdt_entries_offset;
> > >      AcpiXsdtDescriptorRev2 *xsdt;
> > > +    int xsdt_start = table_data->len;
> > >      const unsigned table_data_len = (sizeof(uint64_t) * table_offsets->len);
> > >      const unsigned xsdt_entry_size = sizeof(xsdt->table_offset_entry[0]);
> > >      const size_t xsdt_len = sizeof(*xsdt) + table_data_len;
> > > @@ -1873,7 +1876,8 @@ build_xsdt(GArray *table_data, BIOSLinker *linker, GArray *table_offsets,
> > >              ACPI_BUILD_TABLE_FILE, ref_tbl_offset);
> > >      }
> > >      build_header(linker, table_data,
> > > -                 (void *)xsdt, "XSDT", xsdt_len, 1, oem_id, oem_table_id);
> > > +                 (void *)(table_data->data + xsdt_start),
> > > +                 "XSDT", xsdt_len, 1, oem_id, oem_table_id);
> > >  }
> > >  
> > >  void build_srat_memory(AcpiSratMemoryAffinity *numamem, uint64_t base,
> > > @@ -2053,10 +2057,9 @@ void build_tpm2(GArray *table_data, BIOSLinker *linker, GArray *tcpalog,
> > >      uint64_t control_area_start_address;
> > >      TPMIf *tpmif = tpm_find();
> > >      uint32_t start_method;
> > > -    void *tpm2_ptr;
> > >  
> > >      tpm2_start = table_data->len;
> > > -    tpm2_ptr = acpi_data_push(table_data, sizeof(AcpiTableHeader));
> > > +    acpi_data_push(table_data, sizeof(AcpiTableHeader));
> > >  
> > >      /* Platform Class */
> > >      build_append_int_noprefix(table_data, TPM2_ACPI_CLASS_CLIENT, 2);
> > > @@ -2095,8 +2098,8 @@ void build_tpm2(GArray *table_data, BIOSLinker *linker, GArray *tcpalog,
> > >                                     log_addr_offset, 8,
> > >                                     ACPI_BUILD_TPMLOG_FILE, 0);
> > >      build_header(linker, table_data,
> > > -                 tpm2_ptr, "TPM2", table_data->len - tpm2_start, 4, oem_id,
> > > -                 oem_table_id);
> > > +                 (void *)(table_data->data + tpm2_start),
> > > +                 "TPM2", table_data->len - tpm2_start, 4, oem_id, oem_table_id);
> > >  }
> > >  
> > >  Aml *build_crs(PCIHostState *host, CrsRangeSet *range_set, uint32_t io_offset,
> > > diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
> > > index de98750aef..daaf8f473e 100644
> > > --- a/hw/i386/acpi-build.c
> > > +++ b/hw/i386/acpi-build.c
> > > @@ -1816,6 +1816,7 @@ build_hpet(GArray *table_data, BIOSLinker *linker, const char *oem_id,
> > >             const char *oem_table_id)
> > >  {
> > >      Acpi20Hpet *hpet;
> > > +    int hpet_start = table_data->len;
> > >  
> > >      hpet = acpi_data_push(table_data, sizeof(*hpet));
> > >      /* Note timer_block_id value must be kept in sync with value advertised by
> > > @@ -1824,13 +1825,15 @@ build_hpet(GArray *table_data, BIOSLinker *linker, const char *oem_id,
> > >      hpet->timer_block_id = cpu_to_le32(0x8086a201);
> > >      hpet->addr.address = cpu_to_le64(HPET_BASE);
> > >      build_header(linker, table_data,
> > > -                 (void *)hpet, "HPET", sizeof(*hpet), 1, oem_id, oem_table_id);
> > > +                 (void *)(table_data->data + hpet_start),
> > > +                 "HPET", sizeof(*hpet), 1, oem_id, oem_table_id);
> > >  }
> > >  
> > >  static void
> > >  build_tpm_tcpa(GArray *table_data, BIOSLinker *linker, GArray *tcpalog,
> > >                 const char *oem_id, const char *oem_table_id)
> > >  {
> > > +    int tcpa_start = table_data->len;
> > >      Acpi20Tcpa *tcpa = acpi_data_push(table_data, sizeof *tcpa);
> > >      unsigned log_addr_size = sizeof(tcpa->log_area_start_address);
> > >      unsigned log_addr_offset =
> > > @@ -1849,7 +1852,8 @@ build_tpm_tcpa(GArray *table_data, BIOSLinker *linker, GArray *tcpalog,
> > >          ACPI_BUILD_TPMLOG_FILE, 0);
> > >  
> > >      build_header(linker, table_data,
> > > -                 (void *)tcpa, "TCPA", sizeof(*tcpa), 2, oem_id, oem_table_id);
> > > +                 (void *)(table_data->data + tcpa_start),
> > > +                 "TCPA", sizeof(*tcpa), 2, oem_id, oem_table_id);
> > >  }
> > >  
> > >  #define HOLE_640K_START  (640 * KiB)
> > > -- 
> > > 2.27.0  
> >