kernel-hacking-2024-linux-s.../arch/x86
Frederic Weisbecker 89e45aac42 x86: Fix instruction breakpoint encoding
Lengths and types of breakpoints are encoded in a half byte
into CPU registers. However when we extract these values
and store them, we add a high half byte part to them: 0x40 to the
length and 0x80 to the type.
When that gets reloaded to the CPU registers, the high part
is masked.

While making the instruction breakpoints available for perf,
I zapped that high part on instruction breakpoint encoding
and that broke the arch -> generic translation used by ptrace
instruction breakpoints. Writing dr7 to set an inst breakpoint
was then failing.

There is no apparent reason for these high parts so we could get
rid of them altogether. That's an invasive change though so let's
do that later and for now fix the problem by restoring that inst
breakpoint high part encoding in this sole patch.

Reported-by: Kelvie Wong <kelvie@ieee.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Prasad <prasad@linux.vnet.ibm.com>
Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Cc: Will Deacon <will.deacon@arm.com>
2010-09-17 03:24:13 +02:00
..
boot x86, setup: move isdigit.h to ctype.h, header files on top. 2010-08-02 21:07:20 -07:00
configs defconfig reduction 2010-08-14 22:26:53 +02:00
crypto
ia32 Mark arguments to certain syscalls as being const 2010-08-13 16:53:13 -07:00
include/asm x86: Fix instruction breakpoint encoding 2010-09-17 03:24:13 +02:00
kernel x86: Fix instruction breakpoint encoding 2010-09-17 03:24:13 +02:00
kvm KVM: i8259: fix migration 2010-09-08 14:50:58 -03:00
lguest
lib Merge branch 'x86/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2010-08-13 10:35:48 -07:00
math-emu
mm x86: Fix the address space annotations of iomap_atomic_prot_pfn() 2010-09-05 14:26:14 +02:00
oprofile oprofile: Add Support for Intel CPU Family 6 / Model 22 (Intel Celeron 540) 2010-09-16 12:35:56 +02:00
pci x86/PCI: use for_each_pci_dev() 2010-07-30 09:47:33 -07:00
power x86, tsc, sched: Recompute cyc2ns_offset's during resume from sleep states 2010-08-20 14:59:02 +02:00
tools
vdso Merge branches 'x86-cleanups-for-linus', 'x86-vmware-for-linus', 'x86-mtrr-for-linus', 'x86-apic-for-linus', 'x86-fpu-for-linus' and 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2010-08-06 16:22:59 -07:00
video
xen xen: pvhvm: rename xen_emul_unplug=ignore to =unnnecessary 2010-08-23 11:59:29 +01:00
.gitignore
Kbuild
Kconfig Replace Configure with Enable in description of MAXSMP 2010-08-21 12:38:58 -07:00
Kconfig.cpu
Kconfig.debug
Makefile
Makefile_32.cpu