Stop setting PG_U in bootstrap mappings.

These mappings are never visible to userspace as they get replaced when
the amd64 pmap is bootstrapped, but there is no need to set PG_U in the
first place.

Reviewed by:	alc, kib
MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D24547
This commit is contained in:
Mark Johnston 2020-04-24 13:53:40 +00:00
parent 277cd3983e
commit 5c17092568
3 changed files with 9 additions and 11 deletions

View File

@ -172,15 +172,15 @@ elf64_exec(struct preloaded_file *fp)
for (i = 0; i < 512; i++) {
/* Each slot of the L4 pages points to the same L3 page. */
PT4[i] = (pml4_entry_t)PT3;
PT4[i] |= PG_V | PG_RW | PG_U;
PT4[i] |= PG_V | PG_RW;
/* Each slot of the L3 pages points to the same L2 page. */
PT3[i] = (pdp_entry_t)PT2;
PT3[i] |= PG_V | PG_RW | PG_U;
PT3[i] |= PG_V | PG_RW;
/* The L2 page slots are mapped with 2MB pages for 1GB. */
PT2[i] = i * (2 * 1024 * 1024);
PT2[i] |= PG_V | PG_RW | PG_PS | PG_U;
PT2[i] |= PG_V | PG_RW | PG_PS;
}
printf("Start @ 0x%lx ...\n", ehdr->e_entry);

View File

@ -48,7 +48,6 @@ struct file_format amd64_elf_obj = { elf64_obj_loadfile, elf64_obj_exec };
#define PG_V 0x001
#define PG_RW 0x002
#define PG_U 0x004
#define PG_PS 0x080
typedef uint64_t p4_entry_t;
@ -96,15 +95,15 @@ elf64_exec(struct preloaded_file *fp)
for (i = 0; i < 512; i++) {
/* Each slot of the level 4 pages points to the same level 3 page */
PT4[i] = (p4_entry_t)VTOP((uintptr_t)&PT3[0]);
PT4[i] |= PG_V | PG_RW | PG_U;
PT4[i] |= PG_V | PG_RW;
/* Each slot of the level 3 pages points to the same level 2 page */
PT3[i] = (p3_entry_t)VTOP((uintptr_t)&PT2[0]);
PT3[i] |= PG_V | PG_RW | PG_U;
PT3[i] |= PG_V | PG_RW;
/* The level 2 page slots are mapped with 2MB pages for 1GB. */
PT2[i] = i * (2 * 1024 * 1024);
PT2[i] |= PG_V | PG_RW | PG_PS | PG_U;
PT2[i] |= PG_V | PG_RW | PG_PS;
}
entry_lo = ehdr->e_entry & 0xffffffff;

View File

@ -60,7 +60,6 @@ struct file_format amd64_elf_obj = { elf64_obj_loadfile, elf64_obj_exec };
#define PG_V 0x001
#define PG_RW 0x002
#define PG_U 0x004
#define PG_PS 0x080
typedef uint64_t p4_entry_t;
@ -127,15 +126,15 @@ elf64_exec(struct preloaded_file *fp)
for (i = 0; i < 512; i++) {
/* Each slot of the level 4 pages points to the same level 3 page */
PT4[i] = (p4_entry_t) 0x3000;
PT4[i] |= PG_V | PG_RW | PG_U;
PT4[i] |= PG_V | PG_RW;
/* Each slot of the level 3 pages points to the same level 2 page */
PT3[i] = (p3_entry_t) 0x4000;
PT3[i] |= PG_V | PG_RW | PG_U;
PT3[i] |= PG_V | PG_RW;
/* The level 2 page slots are mapped with 2MB pages for 1GB. */
PT2[i] = i * (2 * 1024 * 1024);
PT2[i] |= PG_V | PG_RW | PG_PS | PG_U;
PT2[i] |= PG_V | PG_RW | PG_PS;
}
#ifdef DEBUG