On Thu, Oct 21, 2021 at 4:49 AM Paolo Bonzini <pbonzini@xxxxxxxxxx> wrote:
>
> Look them up using a gdt_entry_t pointer, so that the address of
> the descriptor is correct even for "odd" selectors (e.g. 0x98).
> Rename the struct from segment_desc64 to system_desc64,
> highlighting that it is only used in the case of S=0 (system
> descriptor). Rename the "limit" bitfield to "limit2", matching
> the convention used for the various parts of the base field.
>
> Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
> ---
> lib/x86/desc.h | 4 ++--
> x86/svm_tests.c | 12 ++++++------
> x86/vmware_backdoors.c | 8 ++++----
> 3 files changed, 12 insertions(+), 12 deletions(-)
>
> diff --git a/lib/x86/desc.h b/lib/x86/desc.h
> index a6ffb38..1755486 100644
> --- a/lib/x86/desc.h
> +++ b/lib/x86/desc.h
> @@ -172,7 +172,7 @@ typedef struct {
> u8 base_high;
> } gdt_entry_t;
>
> -struct segment_desc64 {
> +struct system_desc64 {
> uint16_t limit1;
> uint16_t base1;
> uint8_t base2;
> @@ -183,7 +183,7 @@ struct segment_desc64 {
> uint16_t s:1;
> uint16_t dpl:2;
> uint16_t p:1;
> - uint16_t limit:4;
> + uint16_t limit2:4;
> uint16_t avl:1;
> uint16_t l:1;
> uint16_t db:1;
> diff --git a/x86/svm_tests.c b/x86/svm_tests.c
> index afdd359..2fdb0dc 100644
> --- a/x86/svm_tests.c
> +++ b/x86/svm_tests.c
> @@ -1876,22 +1876,22 @@ static bool reg_corruption_check(struct svm_test *test)
> static void get_tss_entry(void *data)
> {
> struct descriptor_table_ptr gdt;
> - struct segment_desc64 *gdt_table;
> - struct segment_desc64 *tss_entry;
> + gdt_entry_t *gdt_table;
> + struct system_desc64 *tss_entry;
> u16 tr = 0;
>
> sgdt(&gdt);
> tr = str();
> - gdt_table = (struct segment_desc64 *) gdt.base;
> - tss_entry = &gdt_table[tr / sizeof(struct segment_desc64)];
> - *((struct segment_desc64 **)data) = tss_entry;
> + gdt_table = (gdt_entry_t *) gdt.base;
> + tss_entry = (struct system_desc64 *) &gdt_table[tr / 8];
> + *((struct system_desc64 **)data) = tss_entry;
> }
>
> static int orig_cpu_count;
>
> static void init_startup_prepare(struct svm_test *test)
> {
> - struct segment_desc64 *tss_entry;
> + struct system_desc64 *tss_entry;
> int i;
>
> on_cpu(1, get_tss_entry, &tss_entry);
> diff --git a/x86/vmware_backdoors.c b/x86/vmware_backdoors.c
> index b4902a9..b1433cd 100644
> --- a/x86/vmware_backdoors.c
> +++ b/x86/vmware_backdoors.c
> @@ -133,8 +133,8 @@ struct fault_test vmware_backdoor_tests[] = {
> static void set_tss_ioperm(void)
> {
> struct descriptor_table_ptr gdt;
> - struct segment_desc64 *gdt_table;
> - struct segment_desc64 *tss_entry;
> + gdt_entry_t *gdt_table;
> + struct system_desc64 *tss_entry;
> u16 tr = 0;
> tss64_t *tss;
> unsigned char *ioperm_bitmap;
> @@ -142,8 +142,8 @@ static void set_tss_ioperm(void)
>
> sgdt(&gdt);
> tr = str();
> - gdt_table = (struct segment_desc64 *) gdt.base;
> - tss_entry = &gdt_table[tr / sizeof(struct segment_desc64)];
> + gdt_table = (gdt_entry_t *) gdt.base;
> + tss_entry = (struct system_desc64 *) &gdt_table[tr / 8];
> tss_base = ((uint64_t) tss_entry->base1 |
> ((uint64_t) tss_entry->base2 << 16) |
> ((uint64_t) tss_entry->base3 << 24) |
> --
> 2.27.0
>
>
I think this patch series was what was blocking the `uefi` branch from
being merged into the `master` branch. I was just trying to apply it
locally, so I could review it, and now see that it's been merged
already. Any reason not to go ahead and merge the `uefi` branch into
the mainline branch?
