linux/arch
Takao Indoh 9ee27c7639 [IA64] Save I-resources to ia64_sal_os_state
This is a patch related to this discussion.
http://www.spinics.net/lists/linux-ia64/msg07605.html

When INIT is sent, ip/psr/pfs register is stored to the I-resources
(iip/ipsr/ifs registers), and they are copied in the min-state save
area(pmsa_{iip,ipsr,ifs}).

Therefore, in creating pt_regs at ia64_mca_modify_original_stack(),
cr_{iip,ipsr,ifs} should be derived from pmsa_{iip,ipsr,ifs}. But
current code copies pmsa_{xip,xpsr,xfs} to cr_{iip,ipsr,ifs}
when PSR.ic is 0.

finish_pt_regs(struct pt_regs *regs, const pal_min_state_area_t *ms,
                unsigned long *nat)
{
(snip)
        if (ia64_psr(regs)->ic) {
                regs->cr_iip = ms->pmsa_iip;
                regs->cr_ipsr = ms->pmsa_ipsr;
                regs->cr_ifs = ms->pmsa_ifs;
        } else {
                regs->cr_iip = ms->pmsa_xip;
                regs->cr_ipsr = ms->pmsa_xpsr;
                regs->cr_ifs = ms->pmsa_xfs;
        }

It's ok when PSR.ic is not 0. But when PSR.ic is 0, this could be
a problem when we investigate kernel as the value of regs->cr_iip does
not point to where INIT really interrupted.

At first I tried to change finish_pt_regs() so that it uses always
pmsa_{iip,ipsr,ifs} for cr_{iip,ipsr,ifs}, but Keith Owens pointed out
it could cause another problem if I change it.

>The only problem I can think of is an MCA/INIT
>arriving while code like SAVE_MIN or SAVE_REST is executing.  Back
>tracing at that point using pmsa_iip is going to be a problem, you have
>no idea what state the registers or stack are in.

I confirmed he was right, so I decided to keep it as-is and to
save pmsa_{iip,ipsr,ifs} to ia64_sal_os_state for debugging.

An attached patch is just adding new members into ia64_sal_os_state to
save pmsa_{iip,ipsr,ifs}.

Signed-off-by: Takao Indoh <indou.takao@jp.fujitsu.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2009-12-14 16:37:58 -08:00
..
alpha Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6 2009-12-11 15:31:13 -08:00
arm Merge branch 'next-spi' of git://git.secretlab.ca/git/linux-2.6 2009-12-14 10:22:11 -08:00
avr32 Unify sys_mmap* 2009-12-11 06:44:29 -05:00
blackfin Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6 2009-12-11 15:31:13 -08:00
cris Unify sys_mmap* 2009-12-11 06:44:29 -05:00
frv Unify sys_mmap* 2009-12-11 06:44:29 -05:00
h8300 Unify sys_mmap* 2009-12-11 06:44:29 -05:00
ia64 [IA64] Save I-resources to ia64_sal_os_state 2009-12-14 16:37:58 -08:00
m32r Unify sys_mmap* 2009-12-11 06:44:29 -05:00
m68k Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu 2009-12-14 09:58:24 -08:00
m68knommu Unify sys_mmap* 2009-12-11 06:44:29 -05:00
microblaze microblaze: Remove rt_sigsuspend wrapper 2009-12-14 08:45:12 +01:00
mips Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6 2009-12-11 15:31:13 -08:00
mn10300 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu 2009-12-14 09:58:24 -08:00
parisc Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6 2009-12-11 15:31:13 -08:00
powerpc Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu 2009-12-14 09:58:24 -08:00
s390 Unify sys_mmap* 2009-12-11 06:44:29 -05:00
score Add missing alignment check in arch/score sys_mmap() 2009-12-11 06:48:57 -05:00
sh fix broken aliasing checks for MAP_FIXED on sparc32, mips, arm and sh 2009-12-11 06:44:59 -05:00
sparc Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu 2009-12-14 09:58:24 -08:00
um Unify sys_mmap* 2009-12-11 06:44:29 -05:00
x86 Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-12-14 12:36:46 -08:00
xtensa Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6 2009-12-11 15:34:40 -08:00
.gitignore
Kconfig Merge branch 'kvm-updates/2.6.33' of git://git.kernel.org/pub/scm/virt/kvm/kvm 2009-12-08 08:02:38 -08:00