x86/idt: Split idt_data setup out of set_intr_gate()

The code to setup idt_data is needed for early exception handling, but
set_intr_gate() can't be used that early because it has pv-ops in its
code path which don't work that early.

Split out the idt_data initialization part from set_intr_gate() so
that it can be used separately.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lkml.kernel.org/r/20200907131613.12703-29-joro@8bytes.org
This commit is contained in:
Joerg Roedel 2020-09-07 15:15:29 +02:00 committed by Borislav Petkov
parent a7de15d489
commit 4bed2266cc

View File

@ -205,18 +205,24 @@ idt_setup_from_table(gate_desc *idt, const struct idt_data *t, int size, bool sy
}
}
static void init_idt_data(struct idt_data *data, unsigned int n,
const void *addr)
{
BUG_ON(n > 0xFF);
memset(data, 0, sizeof(*data));
data->vector = n;
data->addr = addr;
data->segment = __KERNEL_CS;
data->bits.type = GATE_INTERRUPT;
data->bits.p = 1;
}
static __init void set_intr_gate(unsigned int n, const void *addr)
{
struct idt_data data;
BUG_ON(n > 0xFF);
memset(&data, 0, sizeof(data));
data.vector = n;
data.addr = addr;
data.segment = __KERNEL_CS;
data.bits.type = GATE_INTERRUPT;
data.bits.p = 1;
init_idt_data(&data, n, addr);
idt_setup_from_table(idt_table, &data, 1, false);
}