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vegardingomolnar
vegard
authored and
ingomolnar
committed
x86/asm: Replace magic numbers in GDT descriptors, script-generated change
Actually replace the numeric values by the new symbolic values. I used this to find all the existing users of the GDT_ENTRY*() macros: $ git grep -P 'GDT_ENTRY(_INIT)?\(' Some of the lines will exceed 80 characters, but some of them will be shorter again in the next couple of patches. Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/r/20231219151200.2878271-4-vegard.nossum@oracle.com
1 parent 41ef75c commit 1445f6e

9 files changed

Lines changed: 36 additions & 36 deletions

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‎arch/x86/boot/pm.c‎

Lines changed: 3 additions & 3 deletions
Original file line numberDiff line numberDiff line change
@@ -68,13 +68,13 @@ static void setup_gdt(void)
6868
being 8-byte unaligned. Intel recommends 16 byte alignment. */
6969
static const u64 boot_gdt[] __attribute__((aligned(16))) = {
7070
/* CS: code, read/execute, 4 GB, base 0 */
71-
[GDT_ENTRY_BOOT_CS] = GDT_ENTRY(0xc09b, 0, 0xfffff),
71+
[GDT_ENTRY_BOOT_CS] = GDT_ENTRY(DESC_CODE32 | _DESC_ACCESSED, 0, 0xfffff),
7272
/* DS: data, read/write, 4 GB, base 0 */
73-
[GDT_ENTRY_BOOT_DS] = GDT_ENTRY(0xc093, 0, 0xfffff),
73+
[GDT_ENTRY_BOOT_DS] = GDT_ENTRY(DESC_DATA32 | _DESC_ACCESSED, 0, 0xfffff),
7474
/* TSS: 32-bit tss, 104 bytes, base 4096 */
7575
/* We only have a TSS here to keep Intel VT happy;
7676
we don't actually use it for anything. */
77-
[GDT_ENTRY_BOOT_TSS] = GDT_ENTRY(0x0089, 4096, 103),
77+
[GDT_ENTRY_BOOT_TSS] = GDT_ENTRY(DESC_TSS32, 4096, 103),
7878
};
7979
/* Xen HVM incorrectly stores a pointer to the gdt_ptr, instead
8080
of the gdt_ptr contents. Thus, make it static so it will

‎arch/x86/kernel/apm_32.c‎

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -420,7 +420,7 @@ static DEFINE_MUTEX(apm_mutex);
420420
* This is for buggy BIOS's that refer to (real mode) segment 0x40
421421
* even though they are called in protected mode.
422422
*/
423-
static struct desc_struct bad_bios_desc = GDT_ENTRY_INIT(0x4092,
423+
static struct desc_struct bad_bios_desc = GDT_ENTRY_INIT(DESC_DATA32_BIOS,
424424
(unsigned long)__va(0x400UL), PAGE_SIZE - 0x400 - 1);
425425

426426
static const char driver_version[] = "1.16ac"; /* no spaces */

‎arch/x86/kernel/cpu/common.c‎

Lines changed: 20 additions & 20 deletions
Original file line numberDiff line numberDiff line change
@@ -188,37 +188,37 @@ DEFINE_PER_CPU_PAGE_ALIGNED(struct gdt_page, gdt_page) = { .gdt = {
188188
* TLS descriptors are currently at a different place compared to i386.
189189
* Hopefully nobody expects them at a fixed place (Wine?)
190190
*/
191-
[GDT_ENTRY_KERNEL32_CS] = GDT_ENTRY_INIT(0xc09b, 0, 0xfffff),
192-
[GDT_ENTRY_KERNEL_CS] = GDT_ENTRY_INIT(0xa09b, 0, 0xfffff),
193-
[GDT_ENTRY_KERNEL_DS] = GDT_ENTRY_INIT(0xc093, 0, 0xfffff),
194-
[GDT_ENTRY_DEFAULT_USER32_CS] = GDT_ENTRY_INIT(0xc0fb, 0, 0xfffff),
195-
[GDT_ENTRY_DEFAULT_USER_DS] = GDT_ENTRY_INIT(0xc0f3, 0, 0xfffff),
196-
[GDT_ENTRY_DEFAULT_USER_CS] = GDT_ENTRY_INIT(0xa0fb, 0, 0xfffff),
191+
[GDT_ENTRY_KERNEL32_CS] = GDT_ENTRY_INIT(DESC_CODE32 | _DESC_ACCESSED, 0, 0xfffff),
192+
[GDT_ENTRY_KERNEL_CS] = GDT_ENTRY_INIT(DESC_CODE64 | _DESC_ACCESSED, 0, 0xfffff),
193+
[GDT_ENTRY_KERNEL_DS] = GDT_ENTRY_INIT(DESC_DATA64 | _DESC_ACCESSED, 0, 0xfffff),
194+
[GDT_ENTRY_DEFAULT_USER32_CS] = GDT_ENTRY_INIT(DESC_CODE32 | DESC_USER | _DESC_ACCESSED, 0, 0xfffff),
195+
[GDT_ENTRY_DEFAULT_USER_DS] = GDT_ENTRY_INIT(DESC_DATA64 | DESC_USER | _DESC_ACCESSED, 0, 0xfffff),
196+
[GDT_ENTRY_DEFAULT_USER_CS] = GDT_ENTRY_INIT(DESC_CODE64 | DESC_USER | _DESC_ACCESSED, 0, 0xfffff),
197197
#else
198-
[GDT_ENTRY_KERNEL_CS] = GDT_ENTRY_INIT(0xc09a, 0, 0xfffff),
199-
[GDT_ENTRY_KERNEL_DS] = GDT_ENTRY_INIT(0xc092, 0, 0xfffff),
200-
[GDT_ENTRY_DEFAULT_USER_CS] = GDT_ENTRY_INIT(0xc0fa, 0, 0xfffff),
201-
[GDT_ENTRY_DEFAULT_USER_DS] = GDT_ENTRY_INIT(0xc0f2, 0, 0xfffff),
198+
[GDT_ENTRY_KERNEL_CS] = GDT_ENTRY_INIT(DESC_CODE32, 0, 0xfffff),
199+
[GDT_ENTRY_KERNEL_DS] = GDT_ENTRY_INIT(DESC_DATA32, 0, 0xfffff),
200+
[GDT_ENTRY_DEFAULT_USER_CS] = GDT_ENTRY_INIT(DESC_CODE32 | DESC_USER, 0, 0xfffff),
201+
[GDT_ENTRY_DEFAULT_USER_DS] = GDT_ENTRY_INIT(DESC_DATA32 | DESC_USER, 0, 0xfffff),
202202
/*
203203
* Segments used for calling PnP BIOS have byte granularity.
204204
* They code segments and data segments have fixed 64k limits,
205205
* the transfer segment sizes are set at run time.
206206
*/
207-
[GDT_ENTRY_PNPBIOS_CS32] = GDT_ENTRY_INIT(0x409a, 0, 0xffff),
208-
[GDT_ENTRY_PNPBIOS_CS16] = GDT_ENTRY_INIT(0x009a, 0, 0xffff),
209-
[GDT_ENTRY_PNPBIOS_DS] = GDT_ENTRY_INIT(0x0092, 0, 0xffff),
210-
[GDT_ENTRY_PNPBIOS_TS1] = GDT_ENTRY_INIT(0x0092, 0, 0),
211-
[GDT_ENTRY_PNPBIOS_TS2] = GDT_ENTRY_INIT(0x0092, 0, 0),
207+
[GDT_ENTRY_PNPBIOS_CS32] = GDT_ENTRY_INIT(DESC_CODE32_BIOS, 0, 0xffff),
208+
[GDT_ENTRY_PNPBIOS_CS16] = GDT_ENTRY_INIT(DESC_CODE16, 0, 0xffff),
209+
[GDT_ENTRY_PNPBIOS_DS] = GDT_ENTRY_INIT(DESC_DATA16, 0, 0xffff),
210+
[GDT_ENTRY_PNPBIOS_TS1] = GDT_ENTRY_INIT(DESC_DATA16, 0, 0),
211+
[GDT_ENTRY_PNPBIOS_TS2] = GDT_ENTRY_INIT(DESC_DATA16, 0, 0),
212212
/*
213213
* The APM segments have byte granularity and their bases
214214
* are set at run time. All have 64k limits.
215215
*/
216-
[GDT_ENTRY_APMBIOS_BASE] = GDT_ENTRY_INIT(0x409a, 0, 0xffff),
217-
[GDT_ENTRY_APMBIOS_BASE+1] = GDT_ENTRY_INIT(0x009a, 0, 0xffff),
218-
[GDT_ENTRY_APMBIOS_BASE+2] = GDT_ENTRY_INIT(0x4092, 0, 0xffff),
216+
[GDT_ENTRY_APMBIOS_BASE] = GDT_ENTRY_INIT(DESC_CODE32_BIOS, 0, 0xffff),
217+
[GDT_ENTRY_APMBIOS_BASE+1] = GDT_ENTRY_INIT(DESC_CODE16, 0, 0xffff),
218+
[GDT_ENTRY_APMBIOS_BASE+2] = GDT_ENTRY_INIT(DESC_DATA32_BIOS, 0, 0xffff),
219219

220-
[GDT_ENTRY_ESPFIX_SS] = GDT_ENTRY_INIT(0xc092, 0, 0xfffff),
221-
[GDT_ENTRY_PERCPU] = GDT_ENTRY_INIT(0xc092, 0, 0xfffff),
220+
[GDT_ENTRY_ESPFIX_SS] = GDT_ENTRY_INIT(DESC_DATA32, 0, 0xfffff),
221+
[GDT_ENTRY_PERCPU] = GDT_ENTRY_INIT(DESC_DATA32, 0, 0xfffff),
222222
#endif
223223
} };
224224
EXPORT_PER_CPU_SYMBOL_GPL(gdt_page);

‎arch/x86/kernel/head64.c‎

Lines changed: 3 additions & 3 deletions
Original file line numberDiff line numberDiff line change
@@ -71,9 +71,9 @@ EXPORT_SYMBOL(vmemmap_base);
7171
* GDT used on the boot CPU before switching to virtual addresses.
7272
*/
7373
static struct desc_struct startup_gdt[GDT_ENTRIES] __initdata = {
74-
[GDT_ENTRY_KERNEL32_CS] = GDT_ENTRY_INIT(0xc09b, 0, 0xfffff),
75-
[GDT_ENTRY_KERNEL_CS] = GDT_ENTRY_INIT(0xa09b, 0, 0xfffff),
76-
[GDT_ENTRY_KERNEL_DS] = GDT_ENTRY_INIT(0xc093, 0, 0xfffff),
74+
[GDT_ENTRY_KERNEL32_CS] = GDT_ENTRY_INIT(DESC_CODE32 | _DESC_ACCESSED, 0, 0xfffff),
75+
[GDT_ENTRY_KERNEL_CS] = GDT_ENTRY_INIT(DESC_CODE64 | _DESC_ACCESSED, 0, 0xfffff),
76+
[GDT_ENTRY_KERNEL_DS] = GDT_ENTRY_INIT(DESC_DATA64 | _DESC_ACCESSED, 0, 0xfffff),
7777
};
7878

7979
/*

‎arch/x86/kernel/setup_percpu.c‎

Lines changed: 2 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -106,8 +106,8 @@ void __init pcpu_populate_pte(unsigned long addr)
106106
static inline void setup_percpu_segment(int cpu)
107107
{
108108
#ifdef CONFIG_X86_32
109-
struct desc_struct d = GDT_ENTRY_INIT(0x8092, per_cpu_offset(cpu),
110-
0xFFFFF);
109+
struct desc_struct d = GDT_ENTRY_INIT(DESC_DATA32 & ~_DESC_DB,
110+
per_cpu_offset(cpu), 0xFFFFF);
111111

112112
write_gdt_entry(get_cpu_gdt_rw(cpu), GDT_ENTRY_PERCPU, &d, DESCTYPE_S);
113113
#endif

‎arch/x86/platform/pvh/head.S‎

Lines changed: 3 additions & 3 deletions
Original file line numberDiff line numberDiff line change
@@ -149,11 +149,11 @@ SYM_DATA_END(gdt)
149149
SYM_DATA_START_LOCAL(gdt_start)
150150
.quad 0x0000000000000000 /* NULL descriptor */
151151
#ifdef CONFIG_X86_64
152-
.quad GDT_ENTRY(0xa09a, 0, 0xfffff) /* PVH_CS_SEL */
152+
.quad GDT_ENTRY(DESC_CODE64, 0, 0xfffff) /* PVH_CS_SEL */
153153
#else
154-
.quad GDT_ENTRY(0xc09a, 0, 0xfffff) /* PVH_CS_SEL */
154+
.quad GDT_ENTRY(DESC_CODE32, 0, 0xfffff) /* PVH_CS_SEL */
155155
#endif
156-
.quad GDT_ENTRY(0xc092, 0, 0xfffff) /* PVH_DS_SEL */
156+
.quad GDT_ENTRY(DESC_DATA32, 0, 0xfffff) /* PVH_DS_SEL */
157157
SYM_DATA_END_LABEL(gdt_start, SYM_L_LOCAL, gdt_end)
158158

159159
.balign 16

‎arch/x86/realmode/rm/reboot.S‎

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -154,5 +154,5 @@ SYM_DATA_START(machine_real_restart_gdt)
154154
* base value 0x100; since this is consistent with real mode
155155
* semantics we don't have to reload the segments once CR0.PE = 0.
156156
*/
157-
.quad GDT_ENTRY(0x0093, 0x100, 0xffff)
157+
.quad GDT_ENTRY(DESC_DATA16 | _DESC_ACCESSED, 0x100, 0xffff)
158158
SYM_DATA_END(machine_real_restart_gdt)

‎drivers/firmware/efi/libstub/x86-5lvl.c‎

Lines changed: 2 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -13,8 +13,8 @@ bool efi_no5lvl;
1313
static void (*la57_toggle)(void *cr3);
1414

1515
static const struct desc_struct gdt[] = {
16-
[GDT_ENTRY_KERNEL32_CS] = GDT_ENTRY_INIT(0xc09b, 0, 0xfffff),
17-
[GDT_ENTRY_KERNEL_CS] = GDT_ENTRY_INIT(0xa09b, 0, 0xfffff),
16+
[GDT_ENTRY_KERNEL32_CS] = GDT_ENTRY_INIT(DESC_CODE32 | _DESC_ACCESSED, 0, 0xfffff),
17+
[GDT_ENTRY_KERNEL_CS] = GDT_ENTRY_INIT(DESC_CODE64 | _DESC_ACCESSED, 0, 0xfffff),
1818
};
1919

2020
/*

‎drivers/pnp/pnpbios/bioscalls.c‎

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -60,7 +60,7 @@ do { \
6060
set_desc_limit(&gdt[(selname) >> 3], (size) - 1); \
6161
} while(0)
6262

63-
static struct desc_struct bad_bios_desc = GDT_ENTRY_INIT(0x4092,
63+
static struct desc_struct bad_bios_desc = GDT_ENTRY_INIT(DESC_DATA32_BIOS,
6464
(unsigned long)__va(0x400UL), PAGE_SIZE - 0x400 - 1);
6565

6666
/*

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