search for: get_kernel_rpl

...Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + * + * Send feedback to zach@vmware.com + * + */ + + +#ifndef __MACH_SEGMENT_H +#define __MACH_SEGMENT_H + +#if !defined(CONFIG_X86_VMI) +# error invalid sub-arch include +#endif + +#ifndef __ASSEMBLY__ +static inline unsigned get_kernel_rpl(void) +{ + unsigned cs; + __asm__ ("movl %%cs,%0" : "=r"(cs):); + return cs & SEGMENT_RPL_MASK; +} +#endif + +#define COMPARE_SEGMENT_STACK(segment, offset) \ + pushl %eax; \ + mov offset+4(%esp), %eax; \ + andl $~SEGMENT_RPL_MASK, %eax; \ + cmpw $segment,%ax; \ +...

...Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + * + * Send feedback to zach@vmware.com + * + */ + + +#ifndef __MACH_SEGMENT_H +#define __MACH_SEGMENT_H + +#if !defined(CONFIG_X86_VMI) +# error invalid sub-arch include +#endif + +#ifndef __ASSEMBLY__ +static inline unsigned get_kernel_rpl(void) +{ + unsigned cs; + __asm__ ("movl %%cs,%0" : "=r"(cs):); + return cs & SEGMENT_RPL_MASK; +} +#endif + +#define COMPARE_SEGMENT_STACK(segment, offset) \ + pushl %eax; \ + mov offset+4(%esp), %eax; \ + andl $~SEGMENT_RPL_MASK, %eax; \ + cmpw $segment,%ax; \ +...

...ting %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_MASK 3 2) Add a get_kernel_rpl() macro, and don't assume it's zero. 3) Use USER_RPL macro instead of hardcoded 3 Signed-off-by: Rusty Russell...

...ting %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_MASK 3 2) Add a get_kernel_rpl() macro, and don't assume it's zero. 3) Use USER_RPL macro instead of hardcoded 3 Signed-off-by: Rusty Russell...

Hi, In this patch, I unify segment_32.h and segment_64.h into segment.h They have some common parts, but a considerable ammount of code still has to be around ifdefs. The only patch that is really important to paravirt is the first one, that moves a paravirt definition into the common header. The other two are just normal integration, and pretty much independent

Hi, In this patch, I unify segment_32.h and segment_64.h into segment.h They have some common parts, but a considerable ammount of code still has to be around ifdefs. The only patch that is really important to paravirt is the first one, that moves a paravirt definition into the common header. The other two are just normal integration, and pretty much independent

...Booted on 2.6.16-rc2-git7 Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> This is Zach's patch to clean up assumptions about the kernel running in ring 0 (which it doesn't when running paravirtualized). 1) Remove the hardcoded 3 and introduce #define SEGMENT_RPL_MASK 3 2) Add a get_kernel_rpl() function 3) Create COMPARE_SEGMENT_STACK and COMPARE_SEGMENT_REG macros which can mask out the bottom two bits (RPL) when comparing for paravirtualization. diff -urpN --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal linux-2.6.17-rc2-git7/arch/i386/kernel...

...Booted on 2.6.16-rc2-git7 Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> This is Zach's patch to clean up assumptions about the kernel running in ring 0 (which it doesn't when running paravirtualized). 1) Remove the hardcoded 3 and introduce #define SEGMENT_RPL_MASK 3 2) Add a get_kernel_rpl() function 3) Create COMPARE_SEGMENT_STACK and COMPARE_SEGMENT_REG macros which can mask out the bottom two bits (RPL) when comparing for paravirtualization. diff -urpN --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal linux-2.6.17-rc2-git7/arch/i386/kernel...

...LE_LEVELS 2 diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h index 3d2afecde50c..dedc89a07826 100644 --- a/arch/x86/include/asm/paravirt.h +++ b/arch/x86/include/asm/paravirt.h @@ -160,8 +160,6 @@ static inline void wbinvd(void) PVOP_VCALL0(cpu.wbinvd); } -#define get_kernel_rpl() (pv_info.kernel_rpl) - static inline u64 paravirt_read_msr(unsigned msr) { return PVOP_CALL1(u64, cpu.read_msr, msr); @@ -277,12 +275,10 @@ static inline void load_TLS(struct thread_struct *t, unsigned cpu) PVOP_VCALL2(cpu.load_tls, t, cpu); } -#ifdef CONFIG_X86_64 static inline void l...

...LE_LEVELS 2 diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h index 3d2afecde50c..25c7a73461f6 100644 --- a/arch/x86/include/asm/paravirt.h +++ b/arch/x86/include/asm/paravirt.h @@ -160,8 +160,6 @@ static inline void wbinvd(void) PVOP_VCALL0(cpu.wbinvd); } -#define get_kernel_rpl() (pv_info.kernel_rpl) - static inline u64 paravirt_read_msr(unsigned msr) { return PVOP_CALL1(u64, cpu.read_msr, msr); @@ -277,12 +275,10 @@ static inline void load_TLS(struct thread_struct *t, unsigned cpu) PVOP_VCALL2(cpu.load_tls, t, cpu); } -#ifdef CONFIG_X86_64 static inline void l...

...ded. In normal use, the flags restore > + * in the switch assembly will handle this. But if the kernel > + * is running virtualized at a non-zero CPL, the popf will > + * not restore flags, so it must be done in a separate step. > + */ > + if (get_kernel_rpl() && unlikely(prev->iopl != next->iopl)) > + set_iopl_mask(next->iopl); > +#endif /* CONFIG_X86_IOPORT */ > +} > + > +static inline void switch_io_bitmap(struct tss_struct *tss, > + struct task_struct *prev_p, > + struct task_struct...

...ded. In normal use, the flags restore > + * in the switch assembly will handle this. But if the kernel > + * is running virtualized at a non-zero CPL, the popf will > + * not restore flags, so it must be done in a separate step. > + */ > + if (get_kernel_rpl() && unlikely(prev->iopl != next->iopl)) > + set_iopl_mask(next->iopl); > +#endif /* CONFIG_X86_IOPORT */ > +} > + > +static inline void switch_io_bitmap(struct tss_struct *tss, > + struct task_struct *prev_p, > + struct task_struct...

...(void) -{ - return paravirt_ops.paravirt_enabled; -} +extern int paravirt_enabled; +extern char *paravirt_backend; static inline void load_esp0(struct tss_struct *tss, struct thread_struct *thread) @@ -531,7 +524,12 @@ static inline void wbinvd(void) PVOP_VCALL0(wbinvd); } -#define get_kernel_rpl() (paravirt_ops.kernel_rpl) +#define get_kernel_rpl() \ +({ \ + short kernel_cs; \ + savesegment(cs, kernel_cs); \ + (kernel_cs & SEGMENT_RPL_MASK); \ +}) static inline u64 paravirt_read_msr(unsigned msr, int *err) { @@ -799,6 +797,8 @@ static inline void pte_update_defer(stru...

...(void) -{ - return paravirt_ops.paravirt_enabled; -} +extern int paravirt_enabled; +extern char *paravirt_backend; static inline void load_esp0(struct tss_struct *tss, struct thread_struct *thread) @@ -531,7 +524,12 @@ static inline void wbinvd(void) PVOP_VCALL0(wbinvd); } -#define get_kernel_rpl() (paravirt_ops.kernel_rpl) +#define get_kernel_rpl() \ +({ \ + short kernel_cs; \ + savesegment(cs, kernel_cs); \ + (kernel_cs & SEGMENT_RPL_MASK); \ +}) static inline u64 paravirt_read_msr(unsigned msr, int *err) { @@ -799,6 +797,8 @@ static inline void pte_update_defer(stru...

The long term plan has been to replace Xen PV guests by PVH. The first victim of that plan are now 32-bit PV guests, as those are used only rather seldom these days. Xen on x86 requires 64-bit support and with Grub2 now supporting PVH officially since version 2.04 there is no need to keep 32-bit PV guest support alive in the Linux kernel. Additionally Meltdown mitigation is not available in the

The long term plan has been to replace Xen PV guests by PVH. The first victim of that plan are now 32-bit PV guests, as those are used only rather seldom these days. Xen on x86 requires 64-bit support and with Grub2 now supporting PVH officially since version 2.04 there is no need to keep 32-bit PV guest support alive in the Linux kernel. Additionally Meltdown mitigation is not available in the

The long term plan has been to replace Xen PV guests by PVH. The first victim of that plan are now 32-bit PV guests, as those are used only rather seldom these days. Xen on x86 requires 64-bit support and with Grub2 now supporting PVH officially since version 2.04 there is no need to keep 32-bit PV guest support alive in the Linux kernel. Additionally Meltdown mitigation is not available in the

A lot of cleanup after removal of 32-bit Xen PV guest support in paravirt code. Changes in V4: - dropped patches 1-3, as already committed - addressed comments to V3 - added new patches 5+6 Changes in V3: - addressed comments to V2 - split patch 1 into 2 patches - new patches 3 and 7 Changes in V2: - rebase to 5.8 kernel - addressed comments to V1 - new patches 3 and 4 Juergen Gross (6):

...* Restore IOPL if needed. In normal use, the flags restore + * in the switch assembly will handle this. But if the kernel + * is running virtualized at a non-zero CPL, the popf will + * not restore flags, so it must be done in a separate step. + */ + if (get_kernel_rpl() && unlikely(prev->iopl != next->iopl)) + set_iopl_mask(next->iopl); +#endif /* CONFIG_X86_IOPORT */ +} + +static inline void switch_io_bitmap(struct tss_struct *tss, + struct task_struct *prev_p, + struct task_struct *next_p) +{ +#ifdef CONFIG_X86_IOP...

...* Restore IOPL if needed. In normal use, the flags restore + * in the switch assembly will handle this. But if the kernel + * is running virtualized at a non-zero CPL, the popf will + * not restore flags, so it must be done in a separate step. + */ + if (get_kernel_rpl() && unlikely(prev->iopl != next->iopl)) + set_iopl_mask(next->iopl); +#endif /* CONFIG_X86_IOPORT */ +} + +static inline void switch_io_bitmap(struct tss_struct *tss, + struct task_struct *prev_p, + struct task_struct *next_p) +{ +#ifdef CONFIG_X86_IOP...