Displaying 20 results from an estimated 92 matches for "user_mode".
2006 Jul 05
4
xenoprof passive profiling and "mode" setting
Xiaowei,
I''m puzzled by the following bit of code in p4_check_ctrs():
if (guest_kernel_mode(current, regs))
mode = 1;
else if (ring_0(regs))
mode = 2;
If I look at the definition for guest_kernel_mode() it is:
include/asm-x86/x86_64/regs.h:
#define guest_kernel_mode(v, r) \
(ring_3(r) && ((v)->arch.flags &
2006 Jul 06
0
Fwd: RE: xenoprof passive profiling and "mode" setting
...nt"
<raybry@mpdtxmail.amd.com>
Cc: xen-devel@lists.xensource.com
>guest_kernel_mode() does not work for HVM guests. It may need to be
>fixed -- it had previously only been used in paravirtual-only contexts.
>
>It might make sense to invert[*] the predicate and rename to
>user_mode(). Then definition is simply ring_3(regs) for x86/32 and
>(ring_3(regs) && !((v)->arch.flags & TF_kernel_mode)) for x86/64.
>
>So maybe:
> int mode = 2;
> if (guest_mode(regs))
> mode = user_mode(current, regs) ? 0 : 1;
Yes, this is a better solution for...
2007 Apr 18
2
[patch 3/8] Allow a kernel to not be in ring 0.
...@xensource.com>
We allow for the fact that the guest kernel may not run in ring 0.
This requires some abstraction in a few places when setting %cs or
checking privilege level (user vs kernel).
This is Chris' [RFC PATCH 15/33] move segment checks to subarch,
except rather than using #define USER_MODE_MASK which depends on a
config option, we use Zach's more flexible approach of assuming ring 3
== userspace. I also used "get_kernel_rpl()" over "get_kernel_cs()"
because I think it reads better in the code...
1) Remove the hardcoded 3 and introduce #define SEGMENT_RPL_MAS...
2007 Apr 18
2
[patch 3/8] Allow a kernel to not be in ring 0.
...@xensource.com>
We allow for the fact that the guest kernel may not run in ring 0.
This requires some abstraction in a few places when setting %cs or
checking privilege level (user vs kernel).
This is Chris' [RFC PATCH 15/33] move segment checks to subarch,
except rather than using #define USER_MODE_MASK which depends on a
config option, we use Zach's more flexible approach of assuming ring 3
== userspace. I also used "get_kernel_rpl()" over "get_kernel_cs()"
because I think it reads better in the code...
1) Remove the hardcoded 3 and introduce #define SEGMENT_RPL_MAS...
2020 Apr 28
0
[PATCH v3 40/75] x86/sev-es: Compile early handler code into kernel image
...f, 4);
+ if (put_user(d4, target))
+ goto fault;
+ break;
+ case 8:
+ memcpy(&d8, buf, 8);
+ if (put_user(d8, target))
+ goto fault;
+ break;
+ default:
+ WARN_ONCE(1, "%s: Invalid size: %zu\n", __func__, size);
+ return ES_UNSUPPORTED;
+ }
+
+ return ES_OK;
+
+fault:
+ if (user_mode(ctxt->regs))
+ error_code |= X86_PF_USER;
+
+ ctxt->fi.vector = X86_TRAP_PF;
+ ctxt->fi.error_code = error_code;
+ ctxt->fi.cr2 = (unsigned long)dst;
+
+ return ES_EXCEPTION;
+}
+
+static enum es_result vc_read_mem(struct es_em_ctxt *ctxt,
+ char *src, char *buf, size_t size)
+{
+...
2020 Feb 11
0
[PATCH 39/62] x86/sev-es: Harden runtime #VC handler for exceptions from user-space
...instruction (exit-code 0x%02lx IP: 0x%lx)\n",
+ exit_code, regs->ip);
goto fail;
case ES_EXCEPTION:
forward_exception(&ctxt);
@@ -278,10 +278,24 @@ dotraplinkage void do_vmm_communication(struct pt_regs *regs, unsigned long exit
return;
fail:
- show_regs(regs);
+ if (user_mode(regs)) {
+ /*
+ * Do not kill the machine if user-space triggered the
+ * exception. Send SIGBUS instead and let user-space deal with
+ * it.
+ */
+ force_sig_fault(SIGBUS, BUS_OBJERR, (void __user *)0);
+ } else {
+ /* Show some debug info */
+ show_regs(regs);
- while (true)
- halt...
2020 Feb 11
0
[PATCH 50/62] x86/sev-es: Handle VMMCALL Events
...dle_mwait(struct ghcb *ghcb, struct es_em_ctxt *ctxt)
return ghcb_hv_call(ghcb, ctxt, SVM_EXIT_MWAIT, 0, 0);
}
+static enum es_result handle_vmmcall(struct ghcb *ghcb,
+ struct es_em_ctxt *ctxt)
+{
+ enum es_result ret;
+
+ ghcb_set_rax(ghcb, ctxt->regs->ax);
+ ghcb_set_cpl(ghcb, user_mode(ctxt->regs) ? 3 : 0);
+
+ ret = ghcb_hv_call(ghcb, ctxt, SVM_EXIT_VMMCALL, 0, 0);
+ if (ret != ES_OK)
+ return ret;
+
+ if (!ghcb_is_valid_rax(ghcb))
+ return ES_VMM_ERROR;
+
+ ctxt->regs->ax = ghcb->save.rax;
+
+ return ES_OK;
+}
+
static enum es_result handle_vc_exception(struct es...
2020 Feb 11
0
[PATCH 38/62] x86/sev-es: Handle instruction fetches from user-space
..._fetch_insn_byte(struct es_em_ctxt *ctxt,
unsigned int offset,
char *buffer)
{
- char *rip = (char *)ctxt->regs->ip;
-
- /* More checks are needed when we boot to user-space */
- if (!check_kernel(ctxt->regs))
- return ES_UNSUPPORTED;
-
- buffer[offset] = rip[offset];
+ if (user_mode(ctxt->regs)) {
+ unsigned long addr = ctxt->regs->ip + offset;
+ char __user *rip = (char __user *)addr;
+
+ if (unlikely(addr >= TASK_SIZE_MAX))
+ return ES_UNSUPPORTED;
+
+ if (copy_from_user(buffer + offset, rip, 1)) {
+ ctxt->fi.vector = X86_TRAP_PF;
+ ctxt->fi.c...
2020 Apr 28
0
[PATCH v3 49/75] x86/sev-es: Handle instruction fetches from user-space
...ode_insn(struct es_em_ctxt *ctxt)
enum es_result ret;
int res;
- res = vc_fetch_insn_kernel(ctxt, buffer);
- if (unlikely(res == -EFAULT)) {
- ctxt->fi.vector = X86_TRAP_PF;
- ctxt->fi.error_code = 0;
- ctxt->fi.cr2 = ctxt->regs->ip;
- return ES_EXCEPTION;
+ if (!user_mode(ctxt->regs)) {
+ res = vc_fetch_insn_kernel(ctxt, buffer);
+ if (unlikely(res == -EFAULT)) {
+ ctxt->fi.vector = X86_TRAP_PF;
+ ctxt->fi.error_code = 0;
+ ctxt->fi.cr2 = ctxt->regs->ip;
+ return ES_EXCEPTION;
+ }
+
+ insn_init(&ctxt->insn, buffer, MAX...
2020 Jul 14
0
[PATCH v4 63/75] x86/sev-es: Handle #DB Events
...el/sev-es.c
index 8f275e5d1ce7..b0f08d9669f1 100644
--- a/arch/x86/kernel/sev-es.c
+++ b/arch/x86/kernel/sev-es.c
@@ -928,6 +928,14 @@ static enum es_result vc_handle_trap_ac(struct ghcb *ghcb,
return ES_EXCEPTION;
}
+static __always_inline void vc_handle_trap_db(struct pt_regs *regs)
+{
+ if (user_mode(regs))
+ noist_exc_debug(regs);
+ else
+ exc_debug(regs);
+}
+
static enum es_result vc_handle_exitcode(struct es_em_ctxt *ctxt,
struct ghcb *ghcb,
unsigned long exit_code)
@@ -1028,6 +1036,16 @@ DEFINE_IDTENTRY_VC_SAFE_STACK(exc_vmm_communication)
struct ghcb *ghcb;
lockdep_...
2020 Aug 24
0
[PATCH v6 64/76] x86/sev-es: Handle #DB Events
...el/sev-es.c
index ee0950f01590..e1f3ebbcc122 100644
--- a/arch/x86/kernel/sev-es.c
+++ b/arch/x86/kernel/sev-es.c
@@ -922,6 +922,14 @@ static enum es_result vc_handle_trap_ac(struct ghcb *ghcb,
return ES_EXCEPTION;
}
+static __always_inline void vc_handle_trap_db(struct pt_regs *regs)
+{
+ if (user_mode(regs))
+ noist_exc_debug(regs);
+ else
+ exc_debug(regs);
+}
+
static enum es_result vc_handle_exitcode(struct es_em_ctxt *ctxt,
struct ghcb *ghcb,
unsigned long exit_code)
@@ -1033,6 +1041,15 @@ DEFINE_IDTENTRY_VC_SAFE_STACK(exc_vmm_communication)
struct ghcb *ghcb;
lockdep_...
2007 Jan 05
0
[IA64]: noreturn cannot be used if function may return
...3:31 2007 +1100
@@ -77,7 +77,7 @@ void console_print(char *msg)
// called from unaligned.c
////////////////////////////////////
-void die_if_kernel(char *str, struct pt_regs *regs, long err) /* __attribute__ ((noreturn)) */
+void die_if_kernel(char *str, struct pt_regs *regs, long err)
{
if (user_mode(regs))
return;
@@ -88,7 +88,7 @@ void die_if_kernel(char *str, struct pt_
domain_crash_synchronous();
}
-void vmx_die_if_kernel(char *str, struct pt_regs *regs, long err) /* __attribute__ ((noreturn)) */
+void vmx_die_if_kernel(char *str, struct pt_regs *regs, long err)
{
if (vmx_user_mo...
2020 May 20
1
[PATCH v3 51/75] x86/sev-es: Handle MMIO events
On Tue, Apr 28, 2020 at 05:17:01PM +0200, Joerg Roedel wrote:
> From: Tom Lendacky <thomas.lendacky at amd.com>
>
> Add handler for VC exceptions caused by MMIO intercepts. These
> intercepts come along as nested page faults on pages with reserved
> bits set.
>
> Signed-off-by: Tom Lendacky <thomas.lendacky at amd.com>
> [ jroedel at suse.de: Adapt to VC
2007 Apr 18
1
[PATCH] Slight cleanups for x86 ring macros (against rc3-mm2)
...user-space with LDT SS
restore_nocheck:
diff -r d8064f9b5964 include/asm-i386/ptrace.h
--- a/include/asm-i386/ptrace.h Mon Aug 07 13:30:17 2006 +1000
+++ b/include/asm-i386/ptrace.h Mon Aug 07 14:32:11 2006 +1000
@@ -74,11 +74,11 @@ extern void send_sigtrap(struct task_str
*/
static inline int user_mode(struct pt_regs *regs)
{
- return (regs->xcs & SEGMENT_RPL_MASK) == 3;
+ return (regs->xcs & SEGMENT_RPL_MASK) == USER_RPL;
}
static inline int user_mode_vm(struct pt_regs *regs)
{
- return (((regs->xcs & SEGMENT_RPL_MASK) | (regs->eflags & VM_MASK)) >= 3);
+ retur...
2007 Apr 18
1
[PATCH] Slight cleanups for x86 ring macros (against rc3-mm2)
...user-space with LDT SS
restore_nocheck:
diff -r d8064f9b5964 include/asm-i386/ptrace.h
--- a/include/asm-i386/ptrace.h Mon Aug 07 13:30:17 2006 +1000
+++ b/include/asm-i386/ptrace.h Mon Aug 07 14:32:11 2006 +1000
@@ -74,11 +74,11 @@ extern void send_sigtrap(struct task_str
*/
static inline int user_mode(struct pt_regs *regs)
{
- return (regs->xcs & SEGMENT_RPL_MASK) == 3;
+ return (regs->xcs & SEGMENT_RPL_MASK) == USER_RPL;
}
static inline int user_mode_vm(struct pt_regs *regs)
{
- return (((regs->xcs & SEGMENT_RPL_MASK) | (regs->eflags & VM_MASK)) >= 3);
+ retur...
2007 Apr 18
2
[PATCH 19/21] i386 Kprobes semaphore fix
...u
lock_kprobes();
p = get_kprobe(addr);
if (!p) {
+ unsigned char instr;
unlock_kprobes();
if (regs->eflags & VM_MASK) {
/* We are in virtual-8086 mode. Return 0 */
goto no_kprobe;
}
- if (*addr != BREAKPOINT_INSTRUCTION) {
+ instr = BREAKPOINT_INSTRUCTION;
+ if (user_mode(regs))
+ __get_user(instr, (unsigned char __user *) addr);
+ else
+ instr = *addr;
+
+ if (instr != BREAKPOINT_INSTRUCTION) {
/*
* The breakpoint instruction was removed right
* after we hit it. Another cpu has removed
Index: linux-2.6.14-zach-work/arch/i386/kernel/ptrace.c...
2007 Apr 18
2
[PATCH 19/21] i386 Kprobes semaphore fix
...u
lock_kprobes();
p = get_kprobe(addr);
if (!p) {
+ unsigned char instr;
unlock_kprobes();
if (regs->eflags & VM_MASK) {
/* We are in virtual-8086 mode. Return 0 */
goto no_kprobe;
}
- if (*addr != BREAKPOINT_INSTRUCTION) {
+ instr = BREAKPOINT_INSTRUCTION;
+ if (user_mode(regs))
+ __get_user(instr, (unsigned char __user *) addr);
+ else
+ instr = *addr;
+
+ if (instr != BREAKPOINT_INSTRUCTION) {
/*
* The breakpoint instruction was removed right
* after we hit it. Another cpu has removed
Index: linux-2.6.14-zach-work/arch/i386/kernel/ptrace.c...
2011 Jul 27
9
[PATCH 0/5] Collected vdso/vsyscall fixes for 3.1
This fixes various problems that cropped up with the vdso patches.
- Patch 1 fixes an information leak to userspace.
- Patches 2 and 3 fix the kernel build on gold.
- Patches 4 and 5 fix Xen (I hope).
Konrad, could you could test these on Xen and run 'test_vsyscall test' [1]?
I don't have a usable Xen setup.
Also, I'd appreciate a review of patches 4 and 5 from some
2011 Jul 27
9
[PATCH 0/5] Collected vdso/vsyscall fixes for 3.1
This fixes various problems that cropped up with the vdso patches.
- Patch 1 fixes an information leak to userspace.
- Patches 2 and 3 fix the kernel build on gold.
- Patches 4 and 5 fix Xen (I hope).
Konrad, could you could test these on Xen and run 'test_vsyscall test' [1]?
I don't have a usable Xen setup.
Also, I'd appreciate a review of patches 4 and 5 from some
2011 Jul 27
9
[PATCH 0/5] Collected vdso/vsyscall fixes for 3.1
This fixes various problems that cropped up with the vdso patches.
- Patch 1 fixes an information leak to userspace.
- Patches 2 and 3 fix the kernel build on gold.
- Patches 4 and 5 fix Xen (I hope).
Konrad, could you could test these on Xen and run 'test_vsyscall test' [1]?
I don't have a usable Xen setup.
Also, I'd appreciate a review of patches 4 and 5 from some