From: Dave Peterson Date: Sun, 26 Mar 2006 09:38:50 +0000 (-0800) Subject: [PATCH] EDAC: protect memory controller list X-Git-Tag: v2.6.17-rc1~544 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=18dbc337af5d6efd30cb9291e74722c8ad134fd3;p=linux-2.6 [PATCH] EDAC: protect memory controller list - Fix code so we always hold mem_ctls_mutex while we are stepping through the list of mem_ctl_info structures. Otherwise bad things may happen if one task is stepping through the list while another task is modifying it. We may eventually want to use reference counting to manage the mem_ctl_info structures. In the meantime we may as well fix this bug. - Don't disable interrupts while we are walking the list of mem_ctl_info structures in check_mc_devices(). This is unnecessary. Signed-off-by: David S. Peterson Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/drivers/edac/amd76x_edac.c b/drivers/edac/amd76x_edac.c index 821c252d41..87bd8b4d56 100644 --- a/drivers/edac/amd76x_edac.c +++ b/drivers/edac/amd76x_edac.c @@ -314,10 +314,9 @@ static void __devexit amd76x_remove_one(struct pci_dev *pdev) debugf0("%s()\n", __func__); - if ((mci = edac_mc_find_mci_by_pdev(pdev)) == NULL) - return; - if (edac_mc_del_mc(mci)) + if ((mci = edac_mc_del_mc(pdev)) == NULL) return; + edac_mc_free(mci); } diff --git a/drivers/edac/e752x_edac.c b/drivers/edac/e752x_edac.c index 24446542d8..c86db23d3a 100644 --- a/drivers/edac/e752x_edac.c +++ b/drivers/edac/e752x_edac.c @@ -976,10 +976,7 @@ static void __devexit e752x_remove_one(struct pci_dev *pdev) debugf0("%s()\n", __func__); - if ((mci = edac_mc_find_mci_by_pdev(pdev)) == NULL) - return; - - if (edac_mc_del_mc(mci)) + if ((mci = edac_mc_del_mc(pdev)) == NULL) return; pvt = (struct e752x_pvt *) mci->pvt_info; diff --git a/drivers/edac/e7xxx_edac.c b/drivers/edac/e7xxx_edac.c index 8b0da35ae4..9b59c661f4 100644 --- a/drivers/edac/e7xxx_edac.c +++ b/drivers/edac/e7xxx_edac.c @@ -510,12 +510,12 @@ static void __devexit e7xxx_remove_one(struct pci_dev *pdev) debugf0("%s()\n", __func__); - if (((mci = edac_mc_find_mci_by_pdev(pdev)) != 0) && - !edac_mc_del_mc(mci)) { - pvt = (struct e7xxx_pvt *) mci->pvt_info; - pci_dev_put(pvt->bridge_ck); - edac_mc_free(mci); - } + if ((mci = edac_mc_del_mc(pdev)) == NULL) + return; + + pvt = (struct e7xxx_pvt *) mci->pvt_info; + pci_dev_put(pvt->bridge_ck); + edac_mc_free(mci); } diff --git a/drivers/edac/edac_mc.c b/drivers/edac/edac_mc.c index 7ee9419234..ad812a4f8c 100644 --- a/drivers/edac/edac_mc.c +++ b/drivers/edac/edac_mc.c @@ -1370,11 +1370,7 @@ void edac_mc_free(struct mem_ctl_info *mci) kfree(mci); } - - -EXPORT_SYMBOL(edac_mc_find_mci_by_pdev); - -struct mem_ctl_info *edac_mc_find_mci_by_pdev(struct pci_dev *pdev) +static struct mem_ctl_info *find_mci_by_pdev(struct pci_dev *pdev) { struct mem_ctl_info *mci; struct list_head *item; @@ -1401,7 +1397,7 @@ static int add_mc_to_global_list (struct mem_ctl_info *mci) mci->mc_idx = 0; insert_before = &mc_devices; } else { - if (edac_mc_find_mci_by_pdev(mci->pdev)) { + if (find_mci_by_pdev(mci->pdev)) { edac_printk(KERN_WARNING, EDAC_MC, "%s (%s) %s %s already assigned %d\n", mci->pdev->dev.bus_id, @@ -1520,27 +1516,29 @@ EXPORT_SYMBOL(edac_mc_del_mc); /** * edac_mc_del_mc: Remove sysfs entries for specified mci structure and * remove mci structure from global list - * @mci: Pointer to struct mem_ctl_info structure + * @pdev: Pointer to 'struct pci_dev' representing mci structure to remove. * - * Returns: - * 0 Success - * 1 Failure + * Return pointer to removed mci structure, or NULL if device not found. */ -int edac_mc_del_mc(struct mem_ctl_info *mci) +struct mem_ctl_info * edac_mc_del_mc(struct pci_dev *pdev) { - int rc = 1; + struct mem_ctl_info *mci; - debugf0("MC%d: %s()\n", mci->mc_idx, __func__); - edac_remove_sysfs_mci_device(mci); + debugf0("MC: %s()\n", __func__); down(&mem_ctls_mutex); + + if ((mci = find_mci_by_pdev(pdev)) == NULL) { + up(&mem_ctls_mutex); + return NULL; + } + + edac_remove_sysfs_mci_device(mci); del_mc_from_global_list(mci); + up(&mem_ctls_mutex); edac_printk(KERN_INFO, EDAC_MC, "Removed device %d for %s %s: PCI %s\n", mci->mc_idx, mci->mod_name, mci->ctl_name, pci_name(mci->pdev)); - rc = 0; - up(&mem_ctls_mutex); - - return rc; + return mci; } @@ -2018,14 +2016,12 @@ static inline void clear_pci_parity_errors(void) */ static inline void check_mc_devices (void) { - unsigned long flags; struct list_head *item; struct mem_ctl_info *mci; debugf3("%s()\n", __func__); - /* during poll, have interrupts off */ - local_irq_save(flags); + down(&mem_ctls_mutex); list_for_each(item, &mc_devices) { mci = list_entry(item, struct mem_ctl_info, link); @@ -2034,7 +2030,7 @@ static inline void check_mc_devices (void) mci->edac_check(mci); } - local_irq_restore(flags); + up(&mem_ctls_mutex); } diff --git a/drivers/edac/edac_mc.h b/drivers/edac/edac_mc.h index c9c1590db7..2cec157aae 100644 --- a/drivers/edac/edac_mc.h +++ b/drivers/edac/edac_mc.h @@ -410,14 +410,11 @@ void edac_mc_dump_csrow(struct csrow_info *csrow); #endif /* CONFIG_EDAC_DEBUG */ extern int edac_mc_add_mc(struct mem_ctl_info *mci); -extern int edac_mc_del_mc(struct mem_ctl_info *mci); +extern struct mem_ctl_info * edac_mc_del_mc(struct pci_dev *pdev); extern int edac_mc_find_csrow_by_page(struct mem_ctl_info *mci, unsigned long page); -extern struct mem_ctl_info *edac_mc_find_mci_by_pdev(struct pci_dev - *pdev); - extern void edac_mc_scrub_block(unsigned long page, unsigned long offset, u32 size); diff --git a/drivers/edac/i82860_edac.c b/drivers/edac/i82860_edac.c index 942129df02..688854260a 100644 --- a/drivers/edac/i82860_edac.c +++ b/drivers/edac/i82860_edac.c @@ -237,9 +237,10 @@ static void __devexit i82860_remove_one(struct pci_dev *pdev) debugf0("%s()\n", __func__); - mci = edac_mc_find_mci_by_pdev(pdev); - if ((mci != NULL) && (edac_mc_del_mc(mci) == 0)) - edac_mc_free(mci); + if ((mci = edac_mc_del_mc(pdev)) == NULL) + return; + + edac_mc_free(mci); } static const struct pci_device_id i82860_pci_tbl[] __devinitdata = { diff --git a/drivers/edac/i82875p_edac.c b/drivers/edac/i82875p_edac.c index 40ba2be616..aad1900a46 100644 --- a/drivers/edac/i82875p_edac.c +++ b/drivers/edac/i82875p_edac.c @@ -452,7 +452,7 @@ static void __devexit i82875p_remove_one(struct pci_dev *pdev) debugf0("%s()\n", __func__); - if ((mci = edac_mc_find_mci_by_pdev(pdev)) == NULL) + if ((mci = edac_mc_del_mc(pdev)) == NULL) return; pvt = (struct i82875p_pvt *) mci->pvt_info; @@ -467,9 +467,6 @@ static void __devexit i82875p_remove_one(struct pci_dev *pdev) pci_dev_put(pvt->ovrfl_pdev); } - if (edac_mc_del_mc(mci)) - return; - edac_mc_free(mci); } diff --git a/drivers/edac/r82600_edac.c b/drivers/edac/r82600_edac.c index 787a7652c7..5966916d02 100644 --- a/drivers/edac/r82600_edac.c +++ b/drivers/edac/r82600_edac.c @@ -353,9 +353,10 @@ static void __devexit r82600_remove_one(struct pci_dev *pdev) debugf0("%s()\n", __func__); - if (((mci = edac_mc_find_mci_by_pdev(pdev)) != NULL) && - !edac_mc_del_mc(mci)) - edac_mc_free(mci); + if ((mci = edac_mc_del_mc(pdev)) == NULL) + return; + + edac_mc_free(mci); }