search for: insnbuf

...ive.c b/arch/x86/kernel/alternative.c > > index 3344d3382e91..81c577c7deba 100644 > > --- a/arch/x86/kernel/alternative.c > > +++ b/arch/x86/kernel/alternative.c > > @@ -410,20 +410,28 @@ void __init_or_module noinline apply_alternatives(struct alt_instr *start, > > insnbuf_sz = a->replacementlen; > > > > /* > > - * 0xe8 is a relative jump; fix the offset. > > - * > > - * Instruction length is checked before the opcode to avoid > > - * accessing uninitialized bytes for zero-length replacements. > > + * Fix th...

...ive.c b/arch/x86/kernel/alternative.c > > index 3344d3382e91..81c577c7deba 100644 > > --- a/arch/x86/kernel/alternative.c > > +++ b/arch/x86/kernel/alternative.c > > @@ -410,20 +410,28 @@ void __init_or_module noinline apply_alternatives(struct alt_instr *start, > > insnbuf_sz = a->replacementlen; > > > > /* > > - * 0xe8 is a relative jump; fix the offset. > > - * > > - * Instruction length is checked before the opcode to avoid > > - * accessing uninitialized bytes for zero-length replacements. > > + * Fix th...

...eletions(-) diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c index 3344d3382e91..81c577c7deba 100644 --- a/arch/x86/kernel/alternative.c +++ b/arch/x86/kernel/alternative.c @@ -410,20 +410,28 @@ void __init_or_module noinline apply_alternatives(struct alt_instr *start, insnbuf_sz = a->replacementlen; /* - * 0xe8 is a relative jump; fix the offset. - * - * Instruction length is checked before the opcode to avoid - * accessing uninitialized bytes for zero-length replacements. + * Fix the address offsets for call and jump instructions which + * use PC-re...

...2f88f105..f6e24e78633b 100644 --- a/arch/x86/include/asm/paravirt_types.h +++ b/arch/x86/include/asm/paravirt_types.h @@ -84,7 +84,7 @@ struct pv_init_ops { * the number of bytes of code generated, as we nop pad the * rest in generic code. */ - unsigned (*patch)(u8 type, u16 clobber, void *insnbuf, + unsigned (*patch)(u8 type, void *insnbuf, unsigned long addr, unsigned len); } __no_randomize_layout; @@ -370,14 +370,13 @@ extern struct pv_lock_ops pv_lock_ops; unsigned paravirt_patch_ident_32(void *insnbuf, unsigned len); unsigned paravirt_patch_ident_64(void *insnbuf, unsigned...

.../arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c > index 3344d3382e91..81c577c7deba 100644 > --- a/arch/x86/kernel/alternative.c > +++ b/arch/x86/kernel/alternative.c > @@ -410,20 +410,28 @@ void __init_or_module noinline apply_alternatives(struct alt_instr *start, > insnbuf_sz = a->replacementlen; > > /* > - * 0xe8 is a relative jump; fix the offset. > - * > - * Instruction length is checked before the opcode to avoid > - * accessing uninitialized bytes for zero-length replacements. > + * Fix the address offsets for call and jump...

.../include/asm/paravirt_types.h b/arch/x86/include/asm/paravirt_types.h index 180bc0bff0fb..036b2f88f105 100644 --- a/arch/x86/include/asm/paravirt_types.h +++ b/arch/x86/include/asm/paravirt_types.h @@ -370,12 +370,6 @@ extern struct pv_lock_ops pv_lock_ops; unsigned paravirt_patch_ident_32(void *insnbuf, unsigned len); unsigned paravirt_patch_ident_64(void *insnbuf, unsigned len); -unsigned paravirt_patch_call(void *insnbuf, - const void *target, u16 tgt_clobbers, - unsigned long addr, u16 site_clobbers, - unsigned len); -unsigned paravirt_patch_jmp(void *insnbuf, const void...

.../include/asm/paravirt_types.h b/arch/x86/include/asm/paravirt_types.h index 180bc0bff0fb..036b2f88f105 100644 --- a/arch/x86/include/asm/paravirt_types.h +++ b/arch/x86/include/asm/paravirt_types.h @@ -370,12 +370,6 @@ extern struct pv_lock_ops pv_lock_ops; unsigned paravirt_patch_ident_32(void *insnbuf, unsigned len); unsigned paravirt_patch_ident_64(void *insnbuf, unsigned len); -unsigned paravirt_patch_call(void *insnbuf, - const void *target, u16 tgt_clobbers, - unsigned long addr, u16 site_clobbers, - unsigned len); -unsigned paravirt_patch_jmp(void *insnbuf, const void...

...slowpath)(arch_spinlock_t *lock, __ticket_t head); + void (*unlock)(arch_spinlock_t *lock); }; /* This contains all the paravirt structures: we get a convenient @@ -398,6 +399,7 @@ extern struct pv_lock_ops pv_lock_ops; unsigned paravirt_patch_nop(void); unsigned paravirt_patch_ident_32(void *insnbuf, unsigned len); unsigned paravirt_patch_ident_64(void *insnbuf, unsigned len); +unsigned paravirt_patch_unlock(void *insnbuf, unsigned len); unsigned paravirt_patch_ignore(unsigned len); unsigned paravirt_patch_call(void *insnbuf, const void *target, u16 tgt_clobbers, @@ -620,6 +622,12...

...2,8 @@ extern struct pv_lock_ops pv_lock_ops; __visible extern const char start_##ops##_##name[], end_##ops##_##name[]; \ asm(NATIVE_LABEL("start_", ops, name) code NATIVE_LABEL("end_", ops, name)) -unsigned paravirt_patch_nop(void); unsigned paravirt_patch_ident_32(void *insnbuf, unsigned len); unsigned paravirt_patch_ident_64(void *insnbuf, unsigned len); -unsigned paravirt_patch_ignore(unsigned len); unsigned paravirt_patch_call(void *insnbuf, const void *target, u16 tgt_clobbers, unsigned long addr, u16 site_clobbers, diff --git a/arch/x86/kernel/par...

...2,8 @@ extern struct pv_lock_ops pv_lock_ops; __visible extern const char start_##ops##_##name[], end_##ops##_##name[]; \ asm(NATIVE_LABEL("start_", ops, name) code NATIVE_LABEL("end_", ops, name)) -unsigned paravirt_patch_nop(void); unsigned paravirt_patch_ident_32(void *insnbuf, unsigned len); unsigned paravirt_patch_ident_64(void *insnbuf, unsigned len); -unsigned paravirt_patch_ignore(unsigned len); unsigned paravirt_patch_call(void *insnbuf, const void *target, u16 tgt_clobbers, unsigned long addr, u16 site_clobbers, diff --git a/arch/x86/kernel/par...

Hi, all, I have difficulty on setting up lguest. Basic OS info: gcc 4.1.2 glibc: 2.5.1 binutils: 2.17 kernel: 2.6.23-rc1 Following lguest.txt instruction, I build lguest enaled kernel, disable CONFIG_COMPAT_VDSO, the host kernel boot fine, but when booting Qemu image using lguest laucher program, the guest kernel vmlinux panic, attached console.txt is console output, and config.txt is kernel

Hi, all, I have difficulty on setting up lguest. Basic OS info: gcc 4.1.2 glibc: 2.5.1 binutils: 2.17 kernel: 2.6.23-rc1 Following lguest.txt instruction, I build lguest enaled kernel, disable CONFIG_COMPAT_VDSO, the host kernel boot fine, but when booting Qemu image using lguest laucher program, the guest kernel vmlinux panic, attached console.txt is console output, and config.txt is kernel

With virt_spin_lock() being a pvops function the bare metal case can be optimized by patching the call away completely. In case a kernel running as a guest it can decide whether to use paravitualized spinlocks, the current fallback to the unfair test-and-set scheme, or to mimic the bare metal behavior. Juergen Gross (4): paravirt: add generic _paravirt_false() function paravirt: switch

With virt_spin_lock() being a pvops function the bare metal case can be optimized by patching the call away completely. In case a kernel running as a guest it can decide whether to use paravitualized spinlocks, the current fallback to the unfair test-and-set scheme, or to mimic the bare metal behavior. Juergen Gross (4): paravirt: add generic _paravirt_false() function paravirt: switch

...ume that the restore part of an alternative entry > >> is the same size as the save part. Which is true now. > > Why? > > > > Don't you need to know the size of the instruction without save and > restore part? > > + if (a->replacementlen == 6 && *insnbuf == 0xff && *(insnbuf+1) == 0x15) > > Otherwise you'd need another field for the actual instruction length. If we know where the CALL instruction starts, and can verify that it starts with "ff 15", then we know the instruction length: 6 bytes. Right? -- Josh

...ume that the restore part of an alternative entry > >> is the same size as the save part. Which is true now. > > Why? > > > > Don't you need to know the size of the instruction without save and > restore part? > > + if (a->replacementlen == 6 && *insnbuf == 0xff && *(insnbuf+1) == 0x15) > > Otherwise you'd need another field for the actual instruction length. If we know where the CALL instruction starts, and can verify that it starts with "ff 15", then we know the instruction length: 6 bytes. Right? -- Josh

This series removes some no longer needed stuff from paravirt infrastructure and puts large quantities of paravirt ops under a new config option PARAVIRT_XXL which is selected by XEN_PV only. A pvops kernel without XEN_PV being configured is about 2.5% smaller with this series applied. tip commit 5800dc5c19f34e6e03b5adab1282535cb102fafd ("x86/paravirt: Fix spectre-v2 mitigations for

Hi folks, With this series, the bulk of the work of pvops64 is done. Here, I integrate most of the paravirt.c and paravirt.h files, making them applicable to both architectures. CONFIG_PARAVIRT is _not_ present yet. Basically, this code is missing page table integration (patches currently being worked on by Jeremy). Enjoy

Hi folks, With this series, the bulk of the work of pvops64 is done. Here, I integrate most of the paravirt.c and paravirt.h files, making them applicable to both architectures. CONFIG_PARAVIRT is _not_ present yet. Basically, this code is missing page table integration (patches currently being worked on by Jeremy). Enjoy

Paravirtualized spinlocks produce some overhead even if the kernel is running on bare metal. The main reason are the more complex locking and unlocking functions. Especially unlocking is no longer just one instruction but so complex that it is no longer inlined. This patch series addresses this issue by adding two more pvops functions to reduce the size of the inlined spinlock functions. When