Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge tag 'x86_seves_fixes_for_v5.10_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 SEV-ES fixes from Borislav Petkov:
"Three fixes to SEV-ES to correct setting up the new early pagetable on
5-level paging machines, to always map boot_params and the kernel
cmdline, and disable stack protector for ../compressed/head{32,64}.c.
(Arvind Sankar)"
* tag 'x86_seves_fixes_for_v5.10_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/boot/64: Explicitly map boot_params and command line
x86/head/64: Disable stack protection for head$(BITS).o
x86/boot/64: Initialize 5-level paging variables earlier
+40
-16
+3
arch/x86/boot/compressed/head_64.S
+3
arch/x86/boot/compressed/head_64.S
+19
-8
arch/x86/boot/compressed/ident_map_64.c
+19
-8
arch/x86/boot/compressed/ident_map_64.c
···
33
33
#define __PAGE_OFFSET __PAGE_OFFSET_BASE
34
34
#include "../../mm/ident_map.c"
35
35
36
-
#ifdef CONFIG_X86_5LEVEL
37
-
unsigned int __pgtable_l5_enabled;
38
-
unsigned int pgdir_shift = 39;
39
-
unsigned int ptrs_per_p4d = 1;
40
-
#endif
36
+
#define _SETUP
37
+
#include <asm/setup.h> /* For COMMAND_LINE_SIZE */
38
+
#undef _SETUP
39
+
40
+
extern unsigned long get_cmd_line_ptr(void);
41
41
42
42
/* Used by PAGE_KERN* macros: */
43
43
pteval_t __default_kernel_pte_mask __read_mostly = ~0;
···
107
107
}
108
108
109
109
/* Locates and clears a region for a new top level page table. */
110
-
void initialize_identity_maps(void)
110
+
void initialize_identity_maps(void *rmode)
111
111
{
112
+
unsigned long cmdline;
113
+
112
114
/* Exclude the encryption mask from __PHYSICAL_MASK */
113
115
physical_mask &= ~sme_me_mask;
114
116
···
151
149
}
152
150
153
151
/*
154
-
* New page-table is set up - map the kernel image and load it
155
-
* into cr3.
152
+
* New page-table is set up - map the kernel image, boot_params and the
153
+
* command line. The uncompressed kernel requires boot_params and the
154
+
* command line to be mapped in the identity mapping. Map them
155
+
* explicitly here in case the compressed kernel does not touch them,
156
+
* or does not touch all the pages covering them.
156
157
*/
157
158
add_identity_map((unsigned long)_head, (unsigned long)_end);
159
+
boot_params = rmode;
160
+
add_identity_map((unsigned long)boot_params, (unsigned long)(boot_params + 1));
161
+
cmdline = get_cmd_line_ptr();
162
+
add_identity_map(cmdline, cmdline + COMMAND_LINE_SIZE);
163
+
164
+
/* Load the new page-table. */
158
165
write_cr3(top_level_pgt);
159
166
}
160
167
-8
arch/x86/boot/compressed/kaslr.c
-8
arch/x86/boot/compressed/kaslr.c
···
840
840
return;
841
841
}
842
842
843
-
#ifdef CONFIG_X86_5LEVEL
844
-
if (__read_cr4() & X86_CR4_LA57) {
845
-
__pgtable_l5_enabled = 1;
846
-
pgdir_shift = 48;
847
-
ptrs_per_p4d = 512;
848
-
}
849
-
#endif
850
-
851
843
boot_params->hdr.loadflags |= KASLR_FLAG;
852
844
853
845
if (IS_ENABLED(CONFIG_X86_32))
+16
arch/x86/boot/compressed/pgtable_64.c
+16
arch/x86/boot/compressed/pgtable_64.c
···
8
8
#define BIOS_START_MIN 0x20000U /* 128K, less than this is insane */
9
9
#define BIOS_START_MAX 0x9f000U /* 640K, absolute maximum */
10
10
11
+
#ifdef CONFIG_X86_5LEVEL
12
+
/* __pgtable_l5_enabled needs to be in .data to avoid being cleared along with .bss */
13
+
unsigned int __section(.data) __pgtable_l5_enabled;
14
+
unsigned int __section(.data) pgdir_shift = 39;
15
+
unsigned int __section(.data) ptrs_per_p4d = 1;
16
+
#endif
17
+
11
18
struct paging_config {
12
19
unsigned long trampoline_start;
13
20
unsigned long l5_required;
···
205
198
206
199
/* Restore trampoline memory */
207
200
memcpy(trampoline_32bit, trampoline_save, TRAMPOLINE_32BIT_SIZE);
201
+
202
+
/* Initialize variables for 5-level paging */
203
+
#ifdef CONFIG_X86_5LEVEL
204
+
if (__read_cr4() & X86_CR4_LA57) {
205
+
__pgtable_l5_enabled = 1;
206
+
pgdir_shift = 48;
207
+
ptrs_per_p4d = 512;
208
+
}
209
+
#endif
208
210
}