On Wed, Jan 10, 2007 at 04:59:39PM -0600, linas wrote: > > > However, on a Power4 architecture there are errors reported > > in upper layer (we discussed this in one of earlier emails) followed > > by SCSI errors. > > I'm trying to investigate now. I found two distinct power4 bugs. I posted a patch for one yesterday, under the subject heading [PATCH] Urgent: powerpc 2.6.20-rc4 dma broken on non-LPAR pseries This affects only recent mainline kernels; it would not affect older or distro kernels. The other patch is attached below. After some more testing, I'll submit to mainline. --linas Subject: [PATCH] pSeries: EEH improperly enabled for some Power4 systems It appears that EEH is improperly enabled for some Power4 systems. On these systems, the ibm,set-eeh-option returns a value of success even when EEH is not supported on the given node. Thus, an explicit check for support is required. Signed-off-by: Linas Vepstas <linas@xxxxxxxxxxxxxx> ---- arch/powerpc/platforms/pseries/eeh.c | 19 ++++++++++++++++--- 1 file changed, 16 insertions(+), 3 deletions(-) Index: linux-2.6.20-rc4/arch/powerpc/platforms/pseries/eeh.c =================================================================== --- linux-2.6.20-rc4.orig/arch/powerpc/platforms/pseries/eeh.c 2007-01-11 14:15:02.000000000 -0600 +++ linux-2.6.20-rc4/arch/powerpc/platforms/pseries/eeh.c 2007-01-11 15:14:39.000000000 -0600 @@ -748,6 +748,7 @@ struct eeh_early_enable_info { /* Enable eeh for the given device node. */ static void *early_enable_eeh(struct device_node *dn, void *data) { + unsigned int rets[3]; struct eeh_early_enable_info *info = data; int ret; const char *status = get_property(dn, "status", NULL); @@ -804,16 +805,14 @@ static void *early_enable_eeh(struct dev regs[0], info->buid_hi, info->buid_lo, EEH_ENABLE); + enable = 0; if (ret == 0) { - eeh_subsystem_enabled = 1; - pdn->eeh_mode |= EEH_MODE_SUPPORTED; pdn->eeh_config_addr = regs[0]; /* If the newer, better, ibm,get-config-addr-info is supported, * then use that instead. */ pdn->eeh_pe_config_addr = 0; if (ibm_get_config_addr_info != RTAS_UNKNOWN_SERVICE) { - unsigned int rets[2]; ret = rtas_call (ibm_get_config_addr_info, 4, 2, rets, pdn->eeh_config_addr, info->buid_hi, info->buid_lo, @@ -821,6 +820,20 @@ static void *early_enable_eeh(struct dev if (ret == 0) pdn->eeh_pe_config_addr = rets[0]; } + + /* Some older systems (Power4) allow the + * ibm,set-eeh-option call to succeed even on nodes + * where EEH is not supported. Verify support + * explicitly. */ + ret = read_slot_reset_state(pdn, rets); + if ((ret == 0) && (rets[1] == 1)) + enable = 1; + } + + if (enable) { + eeh_subsystem_enabled = 1; + pdn->eeh_mode |= EEH_MODE_SUPPORTED; + #ifdef DEBUG printk(KERN_DEBUG "EEH: %s: eeh enabled, config=%x pe_config=%x\n", dn->full_name, pdn->eeh_config_addr, pdn->eeh_pe_config_addr); - To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html