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
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asm	[IA64] Save I-resources to ia64_sal_os_state	2009-12-14 16:37:58 -08:00