From d53c51f26145657aa7c55fa396f93677e613548d Mon Sep 17 00:00:00 2001 From: Sebastian Ott Date: Wed, 28 Sep 2016 13:36:19 +0200 Subject: [PATCH] s390/cio: fix accidental interrupt enabling during resume Since commit 9f3d6d7 chsc_get_channel_measurement_chars is called with interrupts disabled during resume from hibernate. Since this function used spin_unlock_irq, interrupts have been enabled accidentally. Fix this by using the irqsave variant. Since we can't guarantee the IRQ-enablement state for all (future/ external) callers, change the locking in related functions to prevent similar bugs in the future. Fixes: 9f3d6d7 ("s390/cio: update measurement characteristics") Signed-off-by: Sebastian Ott Reviewed-by: Peter Oberparleiter Signed-off-by: Martin Schwidefsky --- drivers/s390/cio/chsc.c | 20 ++++++++++++-------- 1 file changed, 12 insertions(+), 8 deletions(-) diff --git a/drivers/s390/cio/chsc.c b/drivers/s390/cio/chsc.c index 940e725bde1e..11674698b36d 100644 --- a/drivers/s390/cio/chsc.c +++ b/drivers/s390/cio/chsc.c @@ -95,12 +95,13 @@ struct chsc_ssd_area { int chsc_get_ssd_info(struct subchannel_id schid, struct chsc_ssd_info *ssd) { struct chsc_ssd_area *ssd_area; + unsigned long flags; int ccode; int ret; int i; int mask; - spin_lock_irq(&chsc_page_lock); + spin_lock_irqsave(&chsc_page_lock, flags); memset(chsc_page, 0, PAGE_SIZE); ssd_area = chsc_page; ssd_area->request.length = 0x0010; @@ -144,7 +145,7 @@ int chsc_get_ssd_info(struct subchannel_id schid, struct chsc_ssd_info *ssd) ssd->fla[i] = ssd_area->fla[i]; } out: - spin_unlock_irq(&chsc_page_lock); + spin_unlock_irqrestore(&chsc_page_lock, flags); return ret; } @@ -832,9 +833,10 @@ int __chsc_do_secm(struct channel_subsystem *css, int enable) u32 fmt : 4; u32 : 16; } __attribute__ ((packed)) *secm_area; + unsigned long flags; int ret, ccode; - spin_lock_irq(&chsc_page_lock); + spin_lock_irqsave(&chsc_page_lock, flags); memset(chsc_page, 0, PAGE_SIZE); secm_area = chsc_page; secm_area->request.length = 0x0050; @@ -864,7 +866,7 @@ int __chsc_do_secm(struct channel_subsystem *css, int enable) CIO_CRW_EVENT(2, "chsc: secm failed (rc=%04x)\n", secm_area->response.code); out: - spin_unlock_irq(&chsc_page_lock); + spin_unlock_irqrestore(&chsc_page_lock, flags); return ret; } @@ -992,6 +994,7 @@ chsc_initialize_cmg_chars(struct channel_path *chp, u8 cmcv, int chsc_get_channel_measurement_chars(struct channel_path *chp) { + unsigned long flags; int ccode, ret; struct { @@ -1021,7 +1024,7 @@ int chsc_get_channel_measurement_chars(struct channel_path *chp) if (!css_chsc_characteristics.scmc || !css_chsc_characteristics.secm) return -EINVAL; - spin_lock_irq(&chsc_page_lock); + spin_lock_irqsave(&chsc_page_lock, flags); memset(chsc_page, 0, PAGE_SIZE); scmc_area = chsc_page; scmc_area->request.length = 0x0010; @@ -1053,7 +1056,7 @@ int chsc_get_channel_measurement_chars(struct channel_path *chp) chsc_initialize_cmg_chars(chp, scmc_area->cmcv, (struct cmg_chars *) &scmc_area->data); out: - spin_unlock_irq(&chsc_page_lock); + spin_unlock_irqrestore(&chsc_page_lock, flags); return ret; } @@ -1134,6 +1137,7 @@ struct css_chsc_char css_chsc_characteristics; int __init chsc_determine_css_characteristics(void) { + unsigned long flags; int result; struct { struct chsc_header request; @@ -1146,7 +1150,7 @@ chsc_determine_css_characteristics(void) u32 chsc_char[508]; } __attribute__ ((packed)) *scsc_area; - spin_lock_irq(&chsc_page_lock); + spin_lock_irqsave(&chsc_page_lock, flags); memset(chsc_page, 0, PAGE_SIZE); scsc_area = chsc_page; scsc_area->request.length = 0x0010; @@ -1168,7 +1172,7 @@ chsc_determine_css_characteristics(void) CIO_CRW_EVENT(2, "chsc: scsc failed (rc=%04x)\n", scsc_area->response.code); exit: - spin_unlock_irq(&chsc_page_lock); + spin_unlock_irqrestore(&chsc_page_lock, flags); return result; } -- 2.30.2