search for: head_64

...xception handling will use rd/wrgsbase in paranoid_entry/exit. > Enable the feature to avoid #UD exceptions on boot APs. > > Signed-off-by: Joerg Roedel <jroedel at suse.de> > Link: https://lore.kernel.org/r/20200724160336.5435-38-joro at 8bytes.org > --- > arch/x86/kernel/head_64.S | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S > index 08412f308de3..4622940134a5 100644 > --- a/arch/x86/kernel/head_64.S > +++ b/arch/x86/kernel/head_64.S > @@ -153,6 +153,13 @@ SYM_CODE_START(secondary...

...xception handling will use rd/wrgsbase in paranoid_entry/exit. > Enable the feature to avoid #UD exceptions on boot APs. > > Signed-off-by: Joerg Roedel <jroedel at suse.de> > Link: https://lore.kernel.org/r/20200724160336.5435-38-joro at 8bytes.org > --- > arch/x86/kernel/head_64.S | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S > index 08412f308de3..4622940134a5 100644 > --- a/arch/x86/kernel/head_64.S > +++ b/arch/x86/kernel/head_64.S > @@ -153,6 +153,13 @@ SYM_CODE_START(secondary...

From: Joerg Roedel <jroedel at suse.de> The #VC exception will trigger very early in head_64.S, when the first CPUID instruction is executed. When secondary CPUs boot, they already load the real system IDT, which has the #VC handler configured to be using an IST stack. IST stacks require a TSS to be loaded, to set up the TSS early for bringing up the secondary CPUs. Use the RW version of e...

From: Joerg Roedel <jroedel at suse.de> Load the IDT right after switching to virtual addresses in head_64.S so that the kernel can handle #VC exceptions. Signed-off-by: Joerg Roedel <jroedel at suse.de> Link: https://lore.kernel.org/r/20200724160336.5435-36-joro at 8bytes.org --- arch/x86/include/asm/setup.h | 3 +++ arch/x86/kernel/head64.c | 3 +++ arch/x86/kernel/head_64.S | 5 ++++...

From: Joerg Roedel <jroedel at suse.de> Handling exceptions during boot requires a working GDT. The kernel GDT is not yet ready for use, so install a temporary boot GDT. Signed-off-by: Joerg Roedel <jroedel at suse.de> --- arch/x86/kernel/head_64.S | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index 4bbc770af632..5a3cde971cb7 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -72,6 +72,20 @@ SYM_CODE_START_NOALIGN(startup_64) /*...

...oerg Roedel <jroedel at suse.de> Move the assembly coded dispatch between page-faults and all other exceptions to C code to make it easier to maintain and extend. Signed-off-by: Joerg Roedel <jroedel at suse.de> --- arch/x86/kernel/head64.c | 20 ++++++++++++++++++++ arch/x86/kernel/head_64.S | 11 +---------- 2 files changed, 21 insertions(+), 10 deletions(-) diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c index 7cdfb7113811..d83c62ebaa85 100644 --- a/arch/x86/kernel/head64.c +++ b/arch/x86/kernel/head64.c @@ -36,6 +36,8 @@ #include <asm/microcode.h> #includ...

...e: > > From: Joerg Roedel <jroedel at suse.de> > > Handling exceptions during boot requires a working GDT. The kernel GDT > is not yet ready for use, so install a temporary boot GDT. > > Signed-off-by: Joerg Roedel <jroedel at suse.de> > --- > arch/x86/kernel/head_64.S | 26 ++++++++++++++++++++++++++ > 1 file changed, 26 insertions(+) > > diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S > index 4bbc770af632..5a3cde971cb7 100644 > --- a/arch/x86/kernel/head_64.S > +++ b/arch/x86/kernel/head_64.S > @@ -72,6 +72,20 @@ SYM_CO...

...us GDT. In the case of SEV-ES this is the EFI GDT. To make exception handling work (especially IRET) the CPU needs to switch to a CS value in the current GDT, so jump to __KERNEL_CS after the first GDT is loaded. Signed-off-by: Joerg Roedel <jroedel at suse.de> --- arch/x86/boot/compressed/head_64.S | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S index 4f7e6b84be07..6b11060c3a0f 100644 --- a/arch/x86/boot/compressed/head_64.S +++ b/arch/x86/boot/compressed/head_64.S @@ -393,6 +393,14 @@ SYM_CODE_START(startup...

From: Joerg Roedel <jroedel at suse.de> Handling exceptions during boot requires a working GDT. The kernel GDT is not yet ready for use, so install a temporary boot GDT. Signed-off-by: Joerg Roedel <jroedel at suse.de> --- arch/x86/kernel/head_64.S | 36 ++++++++++++++++++++++++++++++++++++ 1 file changed, 36 insertions(+) diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index 4bbc770af632..11a28c1fb51f 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -72,6 +72,26 @@ SYM_CODE_START_NOALIGN(startup...

From: Joerg Roedel <jroedel at suse.de> The APs are not ready to handle exceptions when verify_cpu() is called in secondary_startup_64. Signed-off-by: Joerg Roedel <jroedel at suse.de> --- arch/x86/include/asm/realmode.h | 1 + arch/x86/kernel/head_64.S | 1 + arch/x86/realmode/init.c | 6 ++++++ 3 files changed, 8 insertions(+) diff --git a/arch/x86/include/asm/realmode.h b/arch/x86/include/asm/realmode.h index 6590394af309..5c97807c38a4 100644 --- a/arch/x86/include/asm/realmode.h +++ b/arch/x86/include/asm/realmode.h @@ -69,6 +6...

From: Joerg Roedel <jroedel at suse.de> Load the GDT right after switching to virtual addresses to make sure there is a defined GDT for exception handling. Signed-off-by: Joerg Roedel <jroedel at suse.de> --- arch/x86/kernel/head_64.S | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index 800053219054..f958d4e4ee08 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -166,6 +166,14 @@ SYM_CODE_START(secondary_startup_...

...Roedel <jroedel at suse.de> When stack-protector is enabled a valid GS_BASE is needed before calling any C code function, because the stack canary is loaded from per-cpu data. Signed-off-by: Joerg Roedel <jroedel at suse.de> --- arch/x86/kernel/head64.c | 7 +++++++ arch/x86/kernel/head_64.S | 8 ++++++++ 2 files changed, 15 insertions(+) diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c index 8c82be44be94..b0ab5627900b 100644 --- a/arch/x86/kernel/head64.c +++ b/arch/x86/kernel/head64.c @@ -36,6 +36,7 @@ #include <asm/microcode.h> #include <asm/kasan.h>...

From: Joerg Roedel <jroedel at suse.de> Make sure segments are properly set up before setting up an IDT and doing anything that might cause a #VC exception. This is later needed for early exception handling. Signed-off-by: Joerg Roedel <jroedel at suse.de> --- arch/x86/kernel/head_64.S | 52 +++++++++++++++++++-------------------- 1 file changed, 26 insertions(+), 26 deletions(-) diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index f958d4e4ee08..057c7bd3eeb6 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -174,6 +174,32 @@ SYM_CODE...

...CPU which boots will have lost its stack because the kernel switched to a new page-table which does not map the real-mode stack anymore. This is needed for handling early #VC exceptions caused by instructions like CPUID. Signed-off-by: Joerg Roedel <jroedel at suse.de> --- arch/x86/kernel/head_64.S | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index 057c7bd3eeb6..a5e1939d1dc9 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -200,6 +200,12 @@ SYM_CODE_START(secondary_startup_64) mo...

From: Joerg Roedel <jroedel at suse.de> The APs are not ready to handle exceptions when verify_cpu() is called in secondary_startup_64. Signed-off-by: Joerg Roedel <jroedel at suse.de> --- arch/x86/include/asm/realmode.h | 1 + arch/x86/kernel/head_64.S | 12 ++++++++++++ arch/x86/realmode/init.c | 6 ++++++ 3 files changed, 19 insertions(+) diff --git a/arch/x86/include/asm/realmode.h b/arch/x86/include/asm/realmode.h index 6590394af309..5c97807c38a4 100644 --- a/arch/x86/include/asm/realmode.h +++ b/arch/x86/include/asm/realmode...

...-handler, because the stage 2 handler needs our own page-tables to be set up, to which calling set_sev_encryption_mask() is a prerequisite. Signed-off-by: Joerg Roedel <jroedel at suse.de> Link: https://lore.kernel.org/r/20200724160336.5435-20-joro at 8bytes.org --- arch/x86/boot/compressed/head_64.S | 8 +++++++- arch/x86/boot/compressed/ident_map_64.c | 3 --- 2 files changed, 7 insertions(+), 4 deletions(-) diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S index 013b29921836..c7fcf60cbd08 100644 --- a/arch/x86/boot/compressed/head_64.S +++ b/arch/x8...

...because the stack canary is loaded from per-cpu data. Signed-off-by: Joerg Roedel <jroedel at suse.de> Reviewed-by: Kees Cook <keescook at chromium.org> Link: https://lore.kernel.org/r/20200724160336.5435-31-joro at 8bytes.org --- arch/x86/kernel/head64.c | 7 +++++++ arch/x86/kernel/head_64.S | 8 ++++++++ 2 files changed, 15 insertions(+) diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c index 8c82be44be94..b0ab5627900b 100644 --- a/arch/x86/kernel/head64.c +++ b/arch/x86/kernel/head64.c @@ -36,6 +36,7 @@ #include <asm/microcode.h> #include <asm/kasan.h>...

...roedel at suse.de> Early exception handling will use rd/wrgsbase in paranoid_entry/exit. Enable the feature to avoid #UD exceptions on boot APs. Signed-off-by: Joerg Roedel <jroedel at suse.de> Link: https://lore.kernel.org/r/20200724160336.5435-38-joro at 8bytes.org --- arch/x86/kernel/head_64.S | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index 08412f308de3..4622940134a5 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -153,6 +153,13 @@ SYM_CODE_START(secondary_startup_64) orl $X86_CR4_LA57, %...

...wrgsbase in paranoid_entry/exit. > > Enable the feature to avoid #UD exceptions on boot APs. > > > > Signed-off-by: Joerg Roedel <jroedel at suse.de> > > Link: https://lore.kernel.org/r/20200724160336.5435-38-joro at 8bytes.org > > --- > > arch/x86/kernel/head_64.S | 7 +++++++ > > 1 file changed, 7 insertions(+) > > > > diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S > > index 08412f308de3..4622940134a5 100644 > > --- a/arch/x86/kernel/head_64.S > > +++ b/arch/x86/kernel/head_64.S > > @@ -153,6...

...e EFI GDT. > > To make exception handling work (especially IRET) the CPU needs to > switch to a CS value in the current GDT, so jump to __KERNEL_CS after > the first GDT is loaded. > > Signed-off-by: Joerg Roedel <jroedel at suse.de> > --- > arch/x86/boot/compressed/head_64.S | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S > index 4f7e6b84be07..6b11060c3a0f 100644 > --- a/arch/x86/boot/compressed/head_64.S > +++ b/arch/x86/boot/compressed/head_64.S > @@ -393,...