From 11190302400dc5825e429e79dda30d59c2d9525a Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Wed, 7 Jan 2015 15:31:29 +0800 Subject: iommu/vt-d: Move iommu preparatory allocations to irq_remap_ops.prepare The whole iommu setup for irq remapping is a convoluted mess. The iommu detect function gets called from mem_init() and the prepare callback gets called from enable_IR_x2apic() for unknown reasons. Of course AMD and Intel setup differs in nonsensical ways. Intels prepare callback is explicit while AMDs prepare callback is implicit in setup_irq_remapping_ops() just to be called in the prepare call again. Because all of this gets called from enable_IR_x2apic() and the dmar prepare function merily parses the ACPI tables, but does not allocate memory we end up with memory allocation from irq disabled context later on. AMDs iommu code at least allocates the required memory from the prepare function. That has issues as well, but thats not scope of this patch. The goal of this change is to distangle the allocation from the actual enablement. There is no point to allocate memory from irq disabled regions with GFP_ATOMIC just because it does not matter at that point in the boot stage. It matters with physical hotplug later on. There is another issue with the current setup. Due to the conversion to stacked irqdomains we end up with a call into the irqdomain allocation code from irq disabled context, but that code does GFP_KERNEL allocations rightfully as there is no reason to do preperatory allocations with GFP_ATOMIC. That change caused the allocator code to complain about GFP_KERNEL allocations invoked in atomic context. Boris provided a temporary hackaround which changed the GFP flags if irq_domain_add() got called from atomic context. Not pretty and we really dont want to get this into a mainline release for obvious reasons. Move the ACPI table parsing and the resulting memory allocations from the enable to the prepare function. That allows to get rid of the horrible hackaround in irq_domain_add() later. [Jiang] Rebased onto v3.19 Signed-off-by: Thomas Gleixner Tested-by: Borislav Petkov Acked-and-tested-by: Joerg Roedel Cc: Tony Luck Cc: iommu@lists.linux-foundation.org Cc: Benjamin Herrenschmidt Cc: Yinghai Lu Cc: x86@kernel.org Link: http://lkml.kernel.org/r/20141205084147.313026156@linutronix.de Link: http://lkml.kernel.org/r/1420615903-28253-3-git-send-email-jiang.liu@linux.intel.com Signed-off-by: Jiang Liu Signed-off-by: Thomas Gleixner --- drivers/iommu/intel_irq_remapping.c | 64 +++++++++++++++++++++++++------------ 1 file changed, 44 insertions(+), 20 deletions(-) (limited to 'drivers/iommu/intel_irq_remapping.c') diff --git a/drivers/iommu/intel_irq_remapping.c b/drivers/iommu/intel_irq_remapping.c index a55b207b9425..2360cb6a8896 100644 --- a/drivers/iommu/intel_irq_remapping.c +++ b/drivers/iommu/intel_irq_remapping.c @@ -595,22 +595,57 @@ static int __init intel_irq_remapping_supported(void) return 1; } -static int __init intel_enable_irq_remapping(void) +static void __init intel_cleanup_irq_remapping(void) +{ + struct dmar_drhd_unit *drhd; + struct intel_iommu *iommu; + + for_each_iommu(iommu, drhd) { + if (ecap_ir_support(iommu->ecap)) { + iommu_disable_irq_remapping(iommu); + intel_teardown_irq_remapping(iommu); + } + } + + if (x2apic_supported()) + pr_warn("Failed to enable irq remapping. You are vulnerable to irq-injection attacks.\n"); +} + +static int __init intel_prepare_irq_remapping(void) { struct dmar_drhd_unit *drhd; struct intel_iommu *iommu; - bool x2apic_present; - int setup = 0; - int eim = 0; - x2apic_present = x2apic_supported(); + if (dmar_table_init() < 0) + return -1; if (parse_ioapics_under_ir() != 1) { - printk(KERN_INFO "Not enable interrupt remapping\n"); + printk(KERN_INFO "Not enabling interrupt remapping\n"); goto error; } - if (x2apic_present) { + for_each_iommu(iommu, drhd) { + if (!ecap_ir_support(iommu->ecap)) + continue; + + /* Do the allocations early */ + if (intel_setup_irq_remapping(iommu)) + goto error; + } + return 0; +error: + intel_cleanup_irq_remapping(); + return -1; +} + +static int __init intel_enable_irq_remapping(void) +{ + struct dmar_drhd_unit *drhd; + struct intel_iommu *iommu; + int setup = 0; + int eim = 0; + + if (x2apic_supported()) { pr_info("Queued invalidation will be enabled to support x2apic and Intr-remapping.\n"); eim = !dmar_x2apic_optout(); @@ -678,9 +713,6 @@ static int __init intel_enable_irq_remapping(void) if (!ecap_ir_support(iommu->ecap)) continue; - if (intel_setup_irq_remapping(iommu)) - goto error; - iommu_set_irq_remapping(iommu, eim); setup = 1; } @@ -702,15 +734,7 @@ static int __init intel_enable_irq_remapping(void) return eim ? IRQ_REMAP_X2APIC_MODE : IRQ_REMAP_XAPIC_MODE; error: - for_each_iommu(iommu, drhd) - if (ecap_ir_support(iommu->ecap)) { - iommu_disable_irq_remapping(iommu); - intel_teardown_irq_remapping(iommu); - } - - if (x2apic_present) - pr_warn("Failed to enable irq remapping. You are vulnerable to irq-injection attacks.\n"); - + intel_cleanup_irq_remapping(); return -1; } @@ -1200,7 +1224,7 @@ static int intel_alloc_hpet_msi(unsigned int irq, unsigned int id) struct irq_remap_ops intel_irq_remap_ops = { .supported = intel_irq_remapping_supported, - .prepare = dmar_table_init, + .prepare = intel_prepare_irq_remapping, .enable = intel_enable_irq_remapping, .disable = disable_irq_remapping, .reenable = reenable_irq_remapping, -- cgit v1.2.3 From e3a981d61d156c1a9ea0aac253d2d3f33c081906 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Wed, 7 Jan 2015 15:31:30 +0800 Subject: iommu/vt-d: Convert allocations to GFP_KERNEL No reason anymore to do GFP_ATOMIC allocations which are not harmful in the normal bootup case, but matter in the physical hotplug scenario. Signed-off-by: Thomas Gleixner Tested-by: Borislav Petkov Acked-and-tested-by: Joerg Roedel Cc: Tony Luck Cc: iommu@lists.linux-foundation.org Cc: Benjamin Herrenschmidt Cc: Yinghai Lu Cc: x86@kernel.org Link: http://lkml.kernel.org/r/20141205084147.472428339@linutronix.de Link: http://lkml.kernel.org/r/1420615903-28253-4-git-send-email-jiang.liu@linux.intel.com Signed-off-by: Jiang Liu Signed-off-by: Thomas Gleixner --- drivers/iommu/intel_irq_remapping.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers/iommu/intel_irq_remapping.c') diff --git a/drivers/iommu/intel_irq_remapping.c b/drivers/iommu/intel_irq_remapping.c index 2360cb6a8896..1e7e09327753 100644 --- a/drivers/iommu/intel_irq_remapping.c +++ b/drivers/iommu/intel_irq_remapping.c @@ -481,11 +481,11 @@ static int intel_setup_irq_remapping(struct intel_iommu *iommu) if (iommu->ir_table) return 0; - ir_table = kzalloc(sizeof(struct ir_table), GFP_ATOMIC); + ir_table = kzalloc(sizeof(struct ir_table), GFP_KERNEL); if (!ir_table) return -ENOMEM; - pages = alloc_pages_node(iommu->node, GFP_ATOMIC | __GFP_ZERO, + pages = alloc_pages_node(iommu->node, GFP_KERNEL | __GFP_ZERO, INTR_REMAP_PAGE_ORDER); if (!pages) { -- cgit v1.2.3 From 2966d9566beb39c53477c96525820b9415de7a7d Mon Sep 17 00:00:00 2001 From: Jiang Liu Date: Wed, 7 Jan 2015 15:31:35 +0800 Subject: iommu/vt-d: Prepare for killing function irq_remapping_supported() Prepare for killing function irq_remapping_supported() by moving code from intel_irq_remapping_supported() into intel_prepare_irq_remapping(). Combined with patch from Joerg at https://lkml.org/lkml/2014/12/15/487, so assume an signed-off from Joerg. Signed-off-by: Jiang Liu Signed-off-by: Joerg Roedel Tested-by: Joerg Roedel Cc: Tony Luck Cc: iommu@lists.linux-foundation.org Cc: Benjamin Herrenschmidt Cc: Yinghai Lu Cc: Borislav Petkov Link: http://lkml.kernel.org/r/1420615903-28253-9-git-send-email-jiang.liu@linux.intel.com Signed-off-by: Thomas Gleixner --- drivers/iommu/intel_irq_remapping.c | 58 ++++++++++++++++--------------------- 1 file changed, 25 insertions(+), 33 deletions(-) (limited to 'drivers/iommu/intel_irq_remapping.c') diff --git a/drivers/iommu/intel_irq_remapping.c b/drivers/iommu/intel_irq_remapping.c index 1e7e09327753..8ccc7aa7e43a 100644 --- a/drivers/iommu/intel_irq_remapping.c +++ b/drivers/iommu/intel_irq_remapping.c @@ -568,30 +568,6 @@ static int __init dmar_x2apic_optout(void) static int __init intel_irq_remapping_supported(void) { - struct dmar_drhd_unit *drhd; - struct intel_iommu *iommu; - - if (disable_irq_remap) - return 0; - if (irq_remap_broken) { - printk(KERN_WARNING - "This system BIOS has enabled interrupt remapping\n" - "on a chipset that contains an erratum making that\n" - "feature unstable. To maintain system stability\n" - "interrupt remapping is being disabled. Please\n" - "contact your BIOS vendor for an update\n"); - add_taint(TAINT_FIRMWARE_WORKAROUND, LOCKDEP_STILL_OK); - disable_irq_remap = 1; - return 0; - } - - if (!dmar_ir_support()) - return 0; - - for_each_iommu(iommu, drhd) - if (!ecap_ir_support(iommu->ecap)) - return 0; - return 1; } @@ -616,26 +592,42 @@ static int __init intel_prepare_irq_remapping(void) struct dmar_drhd_unit *drhd; struct intel_iommu *iommu; + /* First check whether IRQ remapping should be enabled */ + if (disable_irq_remap) + return -ENODEV; + + if (irq_remap_broken) { + printk(KERN_WARNING + "This system BIOS has enabled interrupt remapping\n" + "on a chipset that contains an erratum making that\n" + "feature unstable. To maintain system stability\n" + "interrupt remapping is being disabled. Please\n" + "contact your BIOS vendor for an update\n"); + add_taint(TAINT_FIRMWARE_WORKAROUND, LOCKDEP_STILL_OK); + disable_irq_remap = 1; + return -ENODEV; + } + if (dmar_table_init() < 0) - return -1; + return -ENODEV; + + if (!dmar_ir_support()) + return -ENODEV; if (parse_ioapics_under_ir() != 1) { printk(KERN_INFO "Not enabling interrupt remapping\n"); goto error; } - for_each_iommu(iommu, drhd) { - if (!ecap_ir_support(iommu->ecap)) - continue; - - /* Do the allocations early */ - if (intel_setup_irq_remapping(iommu)) + for_each_iommu(iommu, drhd) + if (!ecap_ir_support(iommu->ecap) || + intel_setup_irq_remapping(iommu)) goto error; - } return 0; + error: intel_cleanup_irq_remapping(); - return -1; + return -ENODEV; } static int __init intel_enable_irq_remapping(void) -- cgit v1.2.3 From 69cf1d8a1286a7bfbeec497b69c43cc7ebb2a787 Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Wed, 7 Jan 2015 15:31:36 +0800 Subject: iommu/vt-d: Allocate IRQ remapping data structures only for all IOMMUs IRQ remapping is only supported when all IOMMUs in the system support it. So check if all IOMMUs in the system support IRQ remapping before doing the allocations. [Jiang] 1) Rebased to v3.19. 2) Remove redundant check of ecap_ir_support(iommu->ecap) in function intel_enable_irq_remapping(). Signed-off-by: Joerg Roedel Signed-off-by: Jiang Liu Tested-by: Joerg Roedel Cc: Tony Luck Cc: iommu@lists.linux-foundation.org Cc: Benjamin Herrenschmidt Cc: Yinghai Lu Cc: Borislav Petkov Link: http://lkml.kernel.org/r/1420615903-28253-10-git-send-email-jiang.liu@linux.intel.com Signed-off-by: Thomas Gleixner --- drivers/iommu/intel_irq_remapping.c | 19 +++++++++---------- 1 file changed, 9 insertions(+), 10 deletions(-) (limited to 'drivers/iommu/intel_irq_remapping.c') diff --git a/drivers/iommu/intel_irq_remapping.c b/drivers/iommu/intel_irq_remapping.c index 8ccc7aa7e43a..137663bd5da2 100644 --- a/drivers/iommu/intel_irq_remapping.c +++ b/drivers/iommu/intel_irq_remapping.c @@ -619,10 +619,16 @@ static int __init intel_prepare_irq_remapping(void) goto error; } + /* First make sure all IOMMUs support IRQ remapping */ for_each_iommu(iommu, drhd) - if (!ecap_ir_support(iommu->ecap) || - intel_setup_irq_remapping(iommu)) + if (!ecap_ir_support(iommu->ecap)) + goto error; + + /* Do the allocations early */ + for_each_iommu(iommu, drhd) + if (intel_setup_irq_remapping(iommu)) goto error; + return 0; error: @@ -673,16 +679,12 @@ static int __init intel_enable_irq_remapping(void) /* * check for the Interrupt-remapping support */ - for_each_iommu(iommu, drhd) { - if (!ecap_ir_support(iommu->ecap)) - continue; - + for_each_iommu(iommu, drhd) if (eim && !ecap_eim_support(iommu->ecap)) { printk(KERN_INFO "DRHD %Lx: EIM not supported by DRHD, " " ecap %Lx\n", drhd->reg_base_addr, iommu->ecap); goto error; } - } /* * Enable queued invalidation for all the DRHD's. @@ -702,9 +704,6 @@ static int __init intel_enable_irq_remapping(void) * Setup Interrupt-remapping for all the DRHD's now. */ for_each_iommu(iommu, drhd) { - if (!ecap_ir_support(iommu->ecap)) - continue; - iommu_set_irq_remapping(iommu, eim); setup = 1; } -- cgit v1.2.3 From 13d09b6603df9df3aa3e410bc2a876889a55c744 Mon Sep 17 00:00:00 2001 From: Jiang Liu Date: Wed, 7 Jan 2015 15:31:37 +0800 Subject: iommu/vt-d: Allow IR works in XAPIC mode though CPU works in X2APIC mode Currently if CPU supports X2APIC, IR hardware must work in X2APIC mode or disabled. Change the code to support IR working in XAPIC mode when CPU supports X2APIC. Then the CPU APIC driver will decide how to handle such as configuration by: 1) Disabling X2APIC mode 2) Forcing X2APIC physical mode This change also fixes a live locking when 1) BIOS enables CPU X2APIC 2) DMAR table disables X2APIC mode or IR hardware doesn't support X2APIC with following messages: [ 37.863463] dmar: INTR-REMAP: Request device [[f0:1f.7] fault index 2 [ 37.863463] INTR-REMAP:[fault reason 36] Detected reserved fields in the IRTE entry [ 37.879372] dmar: INTR-REMAP: Request device [[f0:1f.7] fault index 2 [ 37.879372] INTR-REMAP:[fault reason 36] Detected reserved fields in the IRTE entry [ 37.895282] dmar: INTR-REMAP: Request device [[f0:1f.7] fault index 2 [ 37.895282] INTR-REMAP:[fault reason 36] Detected reserved fields in the IRTE entry [ 37.911192] dmar: INTR-REMAP: Request device [[f0:1f.7] fault index 2 Signed-off-by: Jiang Liu Tested-by: Joerg Roedel Cc: Tony Luck Cc: iommu@lists.linux-foundation.org Cc: Benjamin Herrenschmidt Cc: Yinghai Lu Cc: Borislav Petkov Link: http://lkml.kernel.org/r/1420615903-28253-11-git-send-email-jiang.liu@linux.intel.com Signed-off-by: Thomas Gleixner --- drivers/iommu/intel_irq_remapping.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) (limited to 'drivers/iommu/intel_irq_remapping.c') diff --git a/drivers/iommu/intel_irq_remapping.c b/drivers/iommu/intel_irq_remapping.c index 137663bd5da2..9d67c12c2ffb 100644 --- a/drivers/iommu/intel_irq_remapping.c +++ b/drivers/iommu/intel_irq_remapping.c @@ -32,8 +32,9 @@ struct hpet_scope { }; #define IR_X2APIC_MODE(mode) (mode ? (1 << 11) : 0) -#define IRTE_DEST(dest) ((x2apic_mode) ? dest : dest << 8) +#define IRTE_DEST(dest) ((eim_mode) ? dest : dest << 8) +static int __read_mostly eim_mode; static struct ioapic_scope ir_ioapic[MAX_IO_APICS]; static struct hpet_scope ir_hpet[MAX_HPET_TBS]; @@ -644,8 +645,6 @@ static int __init intel_enable_irq_remapping(void) int eim = 0; if (x2apic_supported()) { - pr_info("Queued invalidation will be enabled to support x2apic and Intr-remapping.\n"); - eim = !dmar_x2apic_optout(); if (!eim) printk(KERN_WARNING @@ -683,8 +682,11 @@ static int __init intel_enable_irq_remapping(void) if (eim && !ecap_eim_support(iommu->ecap)) { printk(KERN_INFO "DRHD %Lx: EIM not supported by DRHD, " " ecap %Lx\n", drhd->reg_base_addr, iommu->ecap); - goto error; + eim = 0; } + eim_mode = eim; + if (eim) + pr_info("Queued invalidation will be enabled to support x2apic and Intr-remapping.\n"); /* * Enable queued invalidation for all the DRHD's. -- cgit v1.2.3 From c392f56c946033bd136043079a62b9188888828d Mon Sep 17 00:00:00 2001 From: Jiang Liu Date: Wed, 7 Jan 2015 15:31:40 +0800 Subject: iommu/irq_remapping: Kill function irq_remapping_supported() and related code Simplify irq_remapping code by killing irq_remapping_supported() and related interfaces. Joerg posted a similar patch at https://lkml.org/lkml/2014/12/15/490, so assume an signed-off from Joerg. Signed-off-by: Jiang Liu Signed-off-by: Joerg Roedel Tested-by: Joerg Roedel Cc: Tony Luck Cc: iommu@lists.linux-foundation.org Cc: H. Peter Anvin Cc: Benjamin Herrenschmidt Cc: Yinghai Lu Cc: Borislav Petkov Cc: David Rientjes Cc: HATAYAMA Daisuke Cc: Jan Beulich Cc: Richard Weinberger Cc: Oren Twaig Link: http://lkml.kernel.org/r/1420615903-28253-14-git-send-email-jiang.liu@linux.intel.com Signed-off-by: Thomas Gleixner --- drivers/iommu/intel_irq_remapping.c | 6 ------ 1 file changed, 6 deletions(-) (limited to 'drivers/iommu/intel_irq_remapping.c') diff --git a/drivers/iommu/intel_irq_remapping.c b/drivers/iommu/intel_irq_remapping.c index 9d67c12c2ffb..fb72bd5f438c 100644 --- a/drivers/iommu/intel_irq_remapping.c +++ b/drivers/iommu/intel_irq_remapping.c @@ -567,11 +567,6 @@ static int __init dmar_x2apic_optout(void) return dmar->flags & DMAR_X2APIC_OPT_OUT; } -static int __init intel_irq_remapping_supported(void) -{ - return 1; -} - static void __init intel_cleanup_irq_remapping(void) { struct dmar_drhd_unit *drhd; @@ -1216,7 +1211,6 @@ static int intel_alloc_hpet_msi(unsigned int irq, unsigned int id) } struct irq_remap_ops intel_irq_remap_ops = { - .supported = intel_irq_remapping_supported, .prepare = intel_prepare_irq_remapping, .enable = intel_enable_irq_remapping, .disable = disable_irq_remapping, -- cgit v1.2.3 From 7fa1c842caca3b1d8a55a64033403cab8ca8583a Mon Sep 17 00:00:00 2001 From: Jiang Liu Date: Wed, 7 Jan 2015 15:31:42 +0800 Subject: iommu/irq_remapping: Change variable disable_irq_remap to be static Change variable disable_irq_remap to be static and simplify the code. Signed-off-by: Jiang Liu Tested-by: Joerg Roedel Cc: Tony Luck Cc: iommu@lists.linux-foundation.org Cc: Benjamin Herrenschmidt Cc: Yinghai Lu Cc: Borislav Petkov Link: http://lkml.kernel.org/r/1420615903-28253-16-git-send-email-jiang.liu@linux.intel.com Signed-off-by: Thomas Gleixner --- drivers/iommu/intel_irq_remapping.c | 5 ----- 1 file changed, 5 deletions(-) (limited to 'drivers/iommu/intel_irq_remapping.c') diff --git a/drivers/iommu/intel_irq_remapping.c b/drivers/iommu/intel_irq_remapping.c index fb72bd5f438c..14de1ab223c8 100644 --- a/drivers/iommu/intel_irq_remapping.c +++ b/drivers/iommu/intel_irq_remapping.c @@ -588,10 +588,6 @@ static int __init intel_prepare_irq_remapping(void) struct dmar_drhd_unit *drhd; struct intel_iommu *iommu; - /* First check whether IRQ remapping should be enabled */ - if (disable_irq_remap) - return -ENODEV; - if (irq_remap_broken) { printk(KERN_WARNING "This system BIOS has enabled interrupt remapping\n" @@ -600,7 +596,6 @@ static int __init intel_prepare_irq_remapping(void) "interrupt remapping is being disabled. Please\n" "contact your BIOS vendor for an update\n"); add_taint(TAINT_FIRMWARE_WORKAROUND, LOCKDEP_STILL_OK); - disable_irq_remap = 1; return -ENODEV; } -- cgit v1.2.3