Module Name: src
Committed By: maxv
Date: Tue Mar 19 19:15:57 UTC 2019
Modified Files:
src/sys/arch/amd64/stand/prekern: locore.S prekern.c trap.S
Log Message:
Fix/remove some half-baked stuff I left in the prekern:
- Page-align the idt store, to be extra sure.
- Remove unneeded prototypes.
- Drop the TSS, we don't care and aren't even using it.
- Initialize %ss with a default value.
- Fix three exception handlers, no need to push an error code.
No actual impact, because these things are used only when returning from
exceptions received in the prekern; these exceptions are not supposed to
be ever received, never are, and if they were we wouldn't return anyway.
To generate a diff of this commit:
cvs rdiff -u -r1.10 -r1.11 src/sys/arch/amd64/stand/prekern/locore.S \
src/sys/arch/amd64/stand/prekern/prekern.c
cvs rdiff -u -r1.4 -r1.5 src/sys/arch/amd64/stand/prekern/trap.S
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/arch/amd64/stand/prekern/locore.S
diff -u src/sys/arch/amd64/stand/prekern/locore.S:1.10 src/sys/arch/amd64/stand/prekern/locore.S:1.11
--- src/sys/arch/amd64/stand/prekern/locore.S:1.10 Sat Mar 9 08:42:25 2019
+++ src/sys/arch/amd64/stand/prekern/locore.S Tue Mar 19 19:15:57 2019
@@ -1,4 +1,4 @@
-/* $NetBSD: locore.S,v 1.10 2019/03/09 08:42:25 maxv Exp $ */
+/* $NetBSD: locore.S,v 1.11 2019/03/19 19:15:57 maxv Exp $ */
/*
* Copyright (c) 1998, 2000, 2007, 2008, 2016, 2017 The NetBSD Foundation, Inc.
@@ -193,8 +193,6 @@ LABEL(gdt64_start)
.quad 0x0000000000000000 /* always empty */
.quad 0x00af9a000000ffff /* kernel CS */
.quad 0x00cf92000000ffff /* kernel DS */
- .quad 0x0000000000000000 /* kernel TSS [1/2] */
- .quad 0x0000000000000000 /* kernel TSS [2/2] */
END(gdt64_start)
gdt64_end:
@@ -569,6 +567,9 @@ longmode:
movw %ax,%gs
movw %ax,%fs
+ movw $GSEL(GDATA_SEL, SEL_KPL),%ax
+ movw %ax,%ss
+
/* The first physical page available. */
leaq (TABLESIZE)(%rsi),%rdi
Index: src/sys/arch/amd64/stand/prekern/prekern.c
diff -u src/sys/arch/amd64/stand/prekern/prekern.c:1.10 src/sys/arch/amd64/stand/prekern/prekern.c:1.11
--- src/sys/arch/amd64/stand/prekern/prekern.c:1.10 Sun Aug 12 12:42:54 2018
+++ src/sys/arch/amd64/stand/prekern/prekern.c Tue Mar 19 19:15:57 2019
@@ -1,4 +1,4 @@
-/* $NetBSD: prekern.c,v 1.10 2018/08/12 12:42:54 maxv Exp $ */
+/* $NetBSD: prekern.c,v 1.11 2019/03/19 19:15:57 maxv Exp $ */
/*
* Copyright (c) 2017 The NetBSD Foundation, Inc. All rights reserved.
@@ -46,15 +46,7 @@ struct bootinfo bootinfo;
extern paddr_t kernpa_start, kernpa_end;
-static uint8_t idtstore[PAGE_SIZE];
-static uint8_t faultstack[PAGE_SIZE];
-static struct x86_64_tss prekern_tss;
-
-/* GDT offsets */
-#define PREKERN_GDT_NUL_OFF (0 * 8)
-#define PREKERN_GDT_CS_OFF (1 * 8)
-#define PREKERN_GDT_DS_OFF (2 * 8)
-#define PREKERN_GDT_TSS_OFF (3 * 8)
+static uint8_t idtstore[PAGE_SIZE] __aligned(PAGE_SIZE);
#define IDTVEC(name) __CONCAT(X, name)
typedef void (vector)(void);
@@ -83,14 +75,6 @@ struct smallframe {
uint64_t sf_ss;
};
-static void setregion(struct region_descriptor *, void *, uint16_t);
-static void setgate(struct gate_descriptor *, void *, int, int, int, int);
-static void set_sys_segment(struct sys_segment_descriptor *, void *,
- size_t, int, int, int);
-static void set_sys_gdt(int, void *, size_t, int, int, int);
-static void init_tss(void);
-static void init_idt(void);
-
void trap(struct smallframe *);
static char *trap_type[] = {
@@ -142,6 +126,8 @@ trap(struct smallframe *sf)
while (1);
}
+/* -------------------------------------------------------------------------- */
+
static void
setregion(struct region_descriptor *rd, void *base, uint16_t limit)
{
@@ -167,42 +153,6 @@ setgate(struct gate_descriptor *gd, void
}
static void
-set_sys_segment(struct sys_segment_descriptor *sd, void *base, size_t limit,
- int type, int dpl, int gran)
-{
- memset(sd, 0, sizeof(*sd));
- sd->sd_lolimit = (unsigned)limit;
- sd->sd_lobase = (uint64_t)base;
- sd->sd_type = type;
- sd->sd_dpl = dpl;
- sd->sd_p = 1;
- sd->sd_hilimit = (unsigned)limit >> 16;
- sd->sd_gran = gran;
- sd->sd_hibase = (uint64_t)base >> 24;
-}
-
-static void
-set_sys_gdt(int slotoff, void *base, size_t limit, int type, int dpl, int gran)
-{
- struct sys_segment_descriptor sd;
- extern uint64_t *gdt64_start;
-
- set_sys_segment(&sd, base, limit, type, dpl, gran);
-
- memcpy(&gdt64_start + slotoff, &sd, sizeof(sd));
-}
-
-static void
-init_tss(void)
-{
- memset(&prekern_tss, 0, sizeof(prekern_tss));
- prekern_tss.tss_ist[0] = (uintptr_t)(&faultstack[PAGE_SIZE-1]) & ~0xf;
-
- set_sys_gdt(PREKERN_GDT_TSS_OFF, &prekern_tss,
- sizeof(struct x86_64_tss) - 1, SDT_SYS386TSS, SEL_KPL, 0);
-}
-
-static void
init_idt(void)
{
struct region_descriptor region;
@@ -331,10 +281,9 @@ init_prekern(paddr_t pa_start)
mm_init(pa_start);
/*
- * Init the TSS and IDT. We mostly don't care about this, they are just
- * here to properly handle traps.
+ * Init the IDT. We mostly don't care about this, it's just here
+ * to properly handle traps.
*/
- init_tss();
init_idt();
print_state(true, "Prekern loaded");
Index: src/sys/arch/amd64/stand/prekern/trap.S
diff -u src/sys/arch/amd64/stand/prekern/trap.S:1.4 src/sys/arch/amd64/stand/prekern/trap.S:1.5
--- src/sys/arch/amd64/stand/prekern/trap.S:1.4 Sat Jul 14 14:29:40 2018
+++ src/sys/arch/amd64/stand/prekern/trap.S Tue Mar 19 19:15:57 2019
@@ -1,4 +1,4 @@
-/* $NetBSD: trap.S,v 1.4 2018/07/14 14:29:40 maxv Exp $ */
+/* $NetBSD: trap.S,v 1.5 2019/03/19 19:15:57 maxv Exp $ */
/*
* Copyright (c) 2017 The NetBSD Foundation, Inc. All rights reserved.
@@ -95,15 +95,15 @@ IDTVEC(trap10)
IDTVEC_END(trap10)
IDTVEC(trap11)
- ZTRAPENTRY(T_SEGNPFLT)
+ TRAPENTRY(T_SEGNPFLT)
IDTVEC_END(trap11)
IDTVEC(trap12)
- ZTRAPENTRY(T_STKFLT)
+ TRAPENTRY(T_STKFLT)
IDTVEC_END(trap12)
IDTVEC(trap13)
- ZTRAPENTRY(T_PROTFLT)
+ TRAPENTRY(T_PROTFLT)
IDTVEC_END(trap13)
IDTVEC(trap14)
