From e3e59876e82a5e1a07f365d5474e7b6943524725 Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Thu, 3 Sep 2009 14:02:10 +0200 Subject: x86/amd-iommu: Dump fault entry on DTE error This patch adds code to dump the content of the device table entry which caused an ILLEGAL_DEV_TABLE_ENTRY error from the IOMMU hardware. Signed-off-by: Joerg Roedel --- arch/x86/kernel/amd_iommu.c | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'arch/x86/kernel') diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c index 6c99f503780..364c6de2637 100644 --- a/arch/x86/kernel/amd_iommu.c +++ b/arch/x86/kernel/amd_iommu.c @@ -138,6 +138,15 @@ static int iommu_has_npcache(struct amd_iommu *iommu) * ****************************************************************************/ +static void dump_dte_entry(u16 devid) +{ + int i; + + for (i = 0; i < 8; ++i) + pr_err("AMD-Vi: DTE[%d]: %08x\n", i, + amd_iommu_dev_table[devid].data[i]); +} + static void iommu_print_event(void *__evt) { u32 *event = __evt; @@ -155,6 +164,7 @@ static void iommu_print_event(void *__evt) "address=0x%016llx flags=0x%04x]\n", PCI_BUS(devid), PCI_SLOT(devid), PCI_FUNC(devid), address, flags); + dump_dte_entry(devid); break; case EVENT_TYPE_IO_FAULT: printk("IO_PAGE_FAULT device=%02x:%02x.%x " -- cgit v1.2.3-70-g09d2 From 945b4ac44e5700acd3d974c176c8ace34b4d2e8e Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Thu, 3 Sep 2009 14:25:02 +0200 Subject: x86/amd-iommu: Dump illegal command on ILLEGAL_COMMAND_ERROR This patch adds code to dump the command which caused an ILLEGAL_COMMAND_ERROR raised by the IOMMU hardware. Signed-off-by: Joerg Roedel --- arch/x86/kernel/amd_iommu.c | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'arch/x86/kernel') diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c index 364c6de2637..e62b35f5df1 100644 --- a/arch/x86/kernel/amd_iommu.c +++ b/arch/x86/kernel/amd_iommu.c @@ -147,6 +147,15 @@ static void dump_dte_entry(u16 devid) amd_iommu_dev_table[devid].data[i]); } +static void dump_command(unsigned long phys_addr) +{ + struct iommu_cmd *cmd = phys_to_virt(phys_addr); + int i; + + for (i = 0; i < 4; ++i) + pr_err("AMD-Vi: CMD[%d]: %08x\n", i, cmd->data[i]); +} + static void iommu_print_event(void *__evt) { u32 *event = __evt; @@ -186,6 +195,7 @@ static void iommu_print_event(void *__evt) break; case EVENT_TYPE_ILL_CMD: printk("ILLEGAL_COMMAND_ERROR address=0x%016llx]\n", address); + dump_command(address); break; case EVENT_TYPE_CMD_HARD_ERR: printk("COMMAND_HARDWARE_ERROR address=0x%016llx " -- cgit v1.2.3-70-g09d2 From e394d72aa8b319211b8f947d151d9d50b0fde842 Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Thu, 3 Sep 2009 15:28:33 +0200 Subject: x86/amd-iommu: Introduce function for iommu-local domain flush This patch introduces a function to flush all domain tlbs for on one given IOMMU. This is required later to reset the command buffer on one IOMMU. Signed-off-by: Joerg Roedel --- arch/x86/kernel/amd_iommu.c | 49 ++++++++++++++++++++++++++++++--------------- 1 file changed, 33 insertions(+), 16 deletions(-) (limited to 'arch/x86/kernel') diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c index e62b35f5df1..64cc582feb9 100644 --- a/arch/x86/kernel/amd_iommu.c +++ b/arch/x86/kernel/amd_iommu.c @@ -465,38 +465,55 @@ static void iommu_flush_tlb_pde(struct amd_iommu *iommu, u16 domid) } /* - * This function is used to flush the IO/TLB for a given protection domain - * on every IOMMU in the system + * This function flushes one domain on one IOMMU */ -static void iommu_flush_domain(u16 domid) +static void flush_domain_on_iommu(struct amd_iommu *iommu, u16 domid) { - unsigned long flags; - struct amd_iommu *iommu; struct iommu_cmd cmd; - - INC_STATS_COUNTER(domain_flush_all); + unsigned long flags; __iommu_build_inv_iommu_pages(&cmd, CMD_INV_IOMMU_ALL_PAGES_ADDRESS, domid, 1, 1); - for_each_iommu(iommu) { - spin_lock_irqsave(&iommu->lock, flags); - __iommu_queue_command(iommu, &cmd); - __iommu_completion_wait(iommu); - __iommu_wait_for_completion(iommu); - spin_unlock_irqrestore(&iommu->lock, flags); - } + spin_lock_irqsave(&iommu->lock, flags); + __iommu_queue_command(iommu, &cmd); + __iommu_completion_wait(iommu); + __iommu_wait_for_completion(iommu); + spin_unlock_irqrestore(&iommu->lock, flags); } -void amd_iommu_flush_all_domains(void) +static void flush_all_domains_on_iommu(struct amd_iommu *iommu) { int i; for (i = 1; i < MAX_DOMAIN_ID; ++i) { if (!test_bit(i, amd_iommu_pd_alloc_bitmap)) continue; - iommu_flush_domain(i); + flush_domain_on_iommu(iommu, i); } + +} + +/* + * This function is used to flush the IO/TLB for a given protection domain + * on every IOMMU in the system + */ +static void iommu_flush_domain(u16 domid) +{ + struct amd_iommu *iommu; + + INC_STATS_COUNTER(domain_flush_all); + + for_each_iommu(iommu) + flush_domain_on_iommu(iommu, domid); +} + +void amd_iommu_flush_all_domains(void) +{ + struct amd_iommu *iommu; + + for_each_iommu(iommu) + flush_all_domains_on_iommu(iommu); } void amd_iommu_flush_all_devices(void) -- cgit v1.2.3-70-g09d2 From f2430bd104bec2706315e9e983a9d9f828ff9565 Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Wed, 26 Aug 2009 12:10:19 +0200 Subject: x86/amd-iommu: Remove some merge helper code This patch removes some left-overs which where put into the code to simplify merging code which also depends on changes in other trees. Signed-off-by: Joerg Roedel --- arch/x86/kernel/amd_iommu.c | 6 ------ 1 file changed, 6 deletions(-) (limited to 'arch/x86/kernel') diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c index 6c99f503780..70fdef54e06 100644 --- a/arch/x86/kernel/amd_iommu.c +++ b/arch/x86/kernel/amd_iommu.c @@ -41,9 +41,7 @@ static DEFINE_RWLOCK(amd_iommu_devtable_lock); static LIST_HEAD(iommu_pd_list); static DEFINE_SPINLOCK(iommu_pd_list_lock); -#ifdef CONFIG_IOMMU_API static struct iommu_ops amd_iommu_ops; -#endif /* * general struct to manage commands send to an IOMMU @@ -62,10 +60,6 @@ static void dma_ops_reserve_addresses(struct dma_ops_domain *dom, unsigned long start_page, unsigned int pages); -#ifndef BUS_NOTIFY_UNBOUND_DRIVER -#define BUS_NOTIFY_UNBOUND_DRIVER 0x0005 -#endif - #ifdef CONFIG_AMD_IOMMU_STATS /* -- cgit v1.2.3-70-g09d2 From 4c6f40d4e0f0bba77a5f27eec4e1c6d1c457d324 Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Tue, 1 Sep 2009 16:43:58 +0200 Subject: x86/amd-iommu: replace "AMD IOMMU" by "AMD-Vi" This patch replaces the "AMD IOMMU" printk strings with the official name for the hardware: "AMD-Vi". Signed-off-by: Joerg Roedel --- arch/x86/include/asm/amd_iommu_types.h | 2 +- arch/x86/kernel/amd_iommu.c | 2 +- arch/x86/kernel/amd_iommu_init.c | 12 ++++++------ 3 files changed, 8 insertions(+), 8 deletions(-) (limited to 'arch/x86/kernel') diff --git a/arch/x86/include/asm/amd_iommu_types.h b/arch/x86/include/asm/amd_iommu_types.h index 0c878caaa0a..106e1305ef8 100644 --- a/arch/x86/include/asm/amd_iommu_types.h +++ b/arch/x86/include/asm/amd_iommu_types.h @@ -198,7 +198,7 @@ extern bool amd_iommu_dump; #define DUMP_printk(format, arg...) \ do { \ if (amd_iommu_dump) \ - printk(KERN_INFO "AMD IOMMU: " format, ## arg); \ + printk(KERN_INFO "AMD-Vi: " format, ## arg); \ } while(0); /* diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c index 70fdef54e06..3e62d783652 100644 --- a/arch/x86/kernel/amd_iommu.c +++ b/arch/x86/kernel/amd_iommu.c @@ -141,7 +141,7 @@ static void iommu_print_event(void *__evt) int flags = (event[1] >> EVENT_FLAGS_SHIFT) & EVENT_FLAGS_MASK; u64 address = (u64)(((u64)event[3]) << 32) | event[2]; - printk(KERN_ERR "AMD IOMMU: Event logged ["); + printk(KERN_ERR "AMD-Vi: Event logged ["); switch (type) { case EVENT_TYPE_ILL_DEV: diff --git a/arch/x86/kernel/amd_iommu_init.c b/arch/x86/kernel/amd_iommu_init.c index c1b17e97252..169958ad624 100644 --- a/arch/x86/kernel/amd_iommu_init.c +++ b/arch/x86/kernel/amd_iommu_init.c @@ -252,7 +252,7 @@ static void __init iommu_feature_disable(struct amd_iommu *iommu, u8 bit) /* Function to enable the hardware */ static void iommu_enable(struct amd_iommu *iommu) { - printk(KERN_INFO "AMD IOMMU: Enabling IOMMU at %s cap 0x%hx\n", + printk(KERN_INFO "AMD-Vi: Enabling IOMMU at %s cap 0x%hx\n", dev_name(&iommu->dev->dev), iommu->cap_ptr); iommu_feature_enable(iommu, CONTROL_IOMMU_EN); @@ -902,7 +902,7 @@ static int __init iommu_setup_msi(struct amd_iommu *iommu) r = request_irq(iommu->dev->irq, amd_iommu_int_handler, IRQF_SAMPLE_RANDOM, - "AMD IOMMU", + "AMD-Vi", NULL); if (r) { @@ -1150,7 +1150,7 @@ int __init amd_iommu_init(void) if (no_iommu) { - printk(KERN_INFO "AMD IOMMU disabled by kernel command line\n"); + printk(KERN_INFO "AMD-Vi disabled by kernel command line\n"); return 0; } @@ -1248,16 +1248,16 @@ int __init amd_iommu_init(void) enable_iommus(); - printk(KERN_INFO "AMD IOMMU: device isolation "); + printk(KERN_INFO "AMD-Vi: device isolation "); if (amd_iommu_isolate) printk("enabled\n"); else printk("disabled\n"); if (amd_iommu_unmap_flush) - printk(KERN_INFO "AMD IOMMU: IO/TLB flush on unmap enabled\n"); + printk(KERN_INFO "AMD-Vi: IO/TLB flush on unmap enabled\n"); else - printk(KERN_INFO "AMD IOMMU: Lazy IO/TLB flushing enabled\n"); + printk(KERN_INFO "AMD-Vi: Lazy IO/TLB flushing enabled\n"); out: return ret; -- cgit v1.2.3-70-g09d2 From ae908c22aa2b9f7d4b41bd02d14e473f79c22dd3 Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Tue, 1 Sep 2009 16:52:16 +0200 Subject: x86/amd-iommu: Remove redundant 'IOMMU' string The 'IOMMU: ' prefix is not necessary because the DUMP_printk macro already prints its own prefix. Signed-off-by: Joerg Roedel --- arch/x86/kernel/amd_iommu_init.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/x86/kernel') diff --git a/arch/x86/kernel/amd_iommu_init.c b/arch/x86/kernel/amd_iommu_init.c index 169958ad624..264b3ef9dd6 100644 --- a/arch/x86/kernel/amd_iommu_init.c +++ b/arch/x86/kernel/amd_iommu_init.c @@ -858,7 +858,7 @@ static int __init init_iommu_all(struct acpi_table_header *table) switch (*p) { case ACPI_IVHD_TYPE: - DUMP_printk("IOMMU: device: %02x:%02x.%01x cap: %04x " + DUMP_printk("device: %02x:%02x.%01x cap: %04x " "seg: %d flags: %01x info %04x\n", PCI_BUS(h->devid), PCI_SLOT(h->devid), PCI_FUNC(h->devid), h->cap_ptr, -- cgit v1.2.3-70-g09d2 From e0faf54ee82bf9c07f0307b4391caad4020bd659 Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Thu, 3 Sep 2009 15:45:51 +0200 Subject: x86/amd-iommu: fix broken check in amd_iommu_flush_all_devices The amd_iommu_pd_table is indexed by protection domain number and not by device id. So this check is broken and must be removed. Cc: stable@kernel.org Signed-off-by: Joerg Roedel --- arch/x86/kernel/amd_iommu.c | 2 -- 1 file changed, 2 deletions(-) (limited to 'arch/x86/kernel') diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c index 3e62d783652..009d722af00 100644 --- a/arch/x86/kernel/amd_iommu.c +++ b/arch/x86/kernel/amd_iommu.c @@ -479,8 +479,6 @@ void amd_iommu_flush_all_devices(void) int i; for (i = 0; i <= amd_iommu_last_bdf; ++i) { - if (amd_iommu_pd_table[i] == NULL) - continue; iommu = amd_iommu_rlookup_table[i]; if (!iommu) -- cgit v1.2.3-70-g09d2 From d586d7852ccd0cecb502bf4809f827e60c486af0 Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Thu, 3 Sep 2009 15:39:23 +0200 Subject: x86/amd-iommu: Add function to flush all DTEs on one IOMMU This function flushes all DTE entries on one IOMMU for all devices behind this IOMMU. This is required for command buffer resetting later. Signed-off-by: Joerg Roedel --- arch/x86/kernel/amd_iommu.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 'arch/x86/kernel') diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c index 64cc582feb9..2dc093370d2 100644 --- a/arch/x86/kernel/amd_iommu.c +++ b/arch/x86/kernel/amd_iommu.c @@ -516,6 +516,19 @@ void amd_iommu_flush_all_domains(void) flush_all_domains_on_iommu(iommu); } +static void flush_all_devices_for_iommu(struct amd_iommu *iommu) +{ + int i; + + for (i = 0; i <= amd_iommu_last_bdf; ++i) { + if (iommu != amd_iommu_rlookup_table[i]) + continue; + + iommu_queue_inv_dev_entry(iommu, i); + iommu_completion_wait(iommu); + } +} + void amd_iommu_flush_all_devices(void) { struct amd_iommu *iommu; -- cgit v1.2.3-70-g09d2 From 93f1cc67cf3196174412adca87321b25c1c986b0 Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Thu, 3 Sep 2009 14:50:20 +0200 Subject: x86/amd-iommu: Add reset function for command buffers This patch factors parts of the command buffer initialization code into a seperate function which can be used to reset the command buffer later. Signed-off-by: Joerg Roedel --- arch/x86/include/asm/amd_iommu_types.h | 3 +++ arch/x86/kernel/amd_iommu_init.c | 20 +++++++++++++++----- 2 files changed, 18 insertions(+), 5 deletions(-) (limited to 'arch/x86/kernel') diff --git a/arch/x86/include/asm/amd_iommu_types.h b/arch/x86/include/asm/amd_iommu_types.h index 0c878caaa0a..c54bc979dc1 100644 --- a/arch/x86/include/asm/amd_iommu_types.h +++ b/arch/x86/include/asm/amd_iommu_types.h @@ -457,4 +457,7 @@ static inline void amd_iommu_stats_init(void) { } #endif /* CONFIG_AMD_IOMMU_STATS */ +/* some function prototypes */ +extern void amd_iommu_reset_cmd_buffer(struct amd_iommu *iommu); + #endif /* _ASM_X86_AMD_IOMMU_TYPES_H */ diff --git a/arch/x86/kernel/amd_iommu_init.c b/arch/x86/kernel/amd_iommu_init.c index c1b17e97252..1752afef948 100644 --- a/arch/x86/kernel/amd_iommu_init.c +++ b/arch/x86/kernel/amd_iommu_init.c @@ -434,6 +434,20 @@ static u8 * __init alloc_command_buffer(struct amd_iommu *iommu) return cmd_buf; } +/* + * This function resets the command buffer if the IOMMU stopped fetching + * commands from it. + */ +void amd_iommu_reset_cmd_buffer(struct amd_iommu *iommu) +{ + iommu_feature_disable(iommu, CONTROL_CMDBUF_EN); + + writel(0x00, iommu->mmio_base + MMIO_CMD_HEAD_OFFSET); + writel(0x00, iommu->mmio_base + MMIO_CMD_TAIL_OFFSET); + + iommu_feature_enable(iommu, CONTROL_CMDBUF_EN); +} + /* * This function writes the command buffer address to the hardware and * enables it. @@ -450,11 +464,7 @@ static void iommu_enable_command_buffer(struct amd_iommu *iommu) memcpy_toio(iommu->mmio_base + MMIO_CMD_BUF_OFFSET, &entry, sizeof(entry)); - /* set head and tail to zero manually */ - writel(0x00, iommu->mmio_base + MMIO_CMD_HEAD_OFFSET); - writel(0x00, iommu->mmio_base + MMIO_CMD_TAIL_OFFSET); - - iommu_feature_enable(iommu, CONTROL_CMDBUF_EN); + amd_iommu_reset_cmd_buffer(iommu); } static void __init free_command_buffer(struct amd_iommu *iommu) -- cgit v1.2.3-70-g09d2 From a345b23b79f1900e7d87c3165182504419180de4 Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Thu, 3 Sep 2009 15:01:43 +0200 Subject: x86/amd-iommu: Reset command buffer on ILLEGAL_COMMAND_ERROR On an ILLEGAL_COMMAND_ERROR the IOMMU stops executing further commands. This patch changes the code to handle this case better by resetting the command buffer in the IOMMU. Signed-off-by: Joerg Roedel --- arch/x86/kernel/amd_iommu.c | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) (limited to 'arch/x86/kernel') diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c index 2dc093370d2..2333d615f5e 100644 --- a/arch/x86/kernel/amd_iommu.c +++ b/arch/x86/kernel/amd_iommu.c @@ -61,6 +61,7 @@ static u64* alloc_pte(struct protection_domain *dom, static void dma_ops_reserve_addresses(struct dma_ops_domain *dom, unsigned long start_page, unsigned int pages); +static void reset_iommu_command_buffer(struct amd_iommu *iommu); #ifndef BUS_NOTIFY_UNBOUND_DRIVER #define BUS_NOTIFY_UNBOUND_DRIVER 0x0005 @@ -156,7 +157,7 @@ static void dump_command(unsigned long phys_addr) pr_err("AMD-Vi: CMD[%d]: %08x\n", i, cmd->data[i]); } -static void iommu_print_event(void *__evt) +static void iommu_print_event(struct amd_iommu *iommu, void *__evt) { u32 *event = __evt; int type = (event[1] >> EVENT_TYPE_SHIFT) & EVENT_TYPE_MASK; @@ -195,6 +196,7 @@ static void iommu_print_event(void *__evt) break; case EVENT_TYPE_ILL_CMD: printk("ILLEGAL_COMMAND_ERROR address=0x%016llx]\n", address); + reset_iommu_command_buffer(iommu); dump_command(address); break; case EVENT_TYPE_CMD_HARD_ERR: @@ -229,7 +231,7 @@ static void iommu_poll_events(struct amd_iommu *iommu) tail = readl(iommu->mmio_base + MMIO_EVT_TAIL_OFFSET); while (head != tail) { - iommu_print_event(iommu->evt_buf + head); + iommu_print_event(iommu, iommu->evt_buf + head); head = (head + EVENT_ENTRY_SIZE) % iommu->evt_buf_size; } @@ -547,6 +549,15 @@ void amd_iommu_flush_all_devices(void) } } +static void reset_iommu_command_buffer(struct amd_iommu *iommu) +{ + pr_err("AMD-Vi: Resetting IOMMU command buffer\n"); + + amd_iommu_reset_cmd_buffer(iommu); + flush_all_devices_for_iommu(iommu); + flush_all_domains_on_iommu(iommu); +} + /**************************************************************************** * * The functions below are used the create the page table mappings for -- cgit v1.2.3-70-g09d2 From b26e81b871bd18184968f0bb3f12945906eadfce Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Thu, 3 Sep 2009 15:08:09 +0200 Subject: x86/amd-iommu: Panic if IOMMU command buffer reset fails To prevent the driver from doing recursive command buffer resets, just panic when that recursion happens. Signed-off-by: Joerg Roedel --- arch/x86/include/asm/amd_iommu_types.h | 3 +++ arch/x86/kernel/amd_iommu.c | 7 +++++++ 2 files changed, 10 insertions(+) (limited to 'arch/x86/kernel') diff --git a/arch/x86/include/asm/amd_iommu_types.h b/arch/x86/include/asm/amd_iommu_types.h index c54bc979dc1..e676746a4a3 100644 --- a/arch/x86/include/asm/amd_iommu_types.h +++ b/arch/x86/include/asm/amd_iommu_types.h @@ -337,6 +337,9 @@ struct amd_iommu { /* if one, we need to send a completion wait command */ bool need_sync; + /* becomes true if a command buffer reset is running */ + bool reset_in_progress; + /* default dma_ops domain for that IOMMU */ struct dma_ops_domain *default_dom; }; diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c index 2333d615f5e..b62a2f64dfc 100644 --- a/arch/x86/kernel/amd_iommu.c +++ b/arch/x86/kernel/amd_iommu.c @@ -553,9 +553,16 @@ static void reset_iommu_command_buffer(struct amd_iommu *iommu) { pr_err("AMD-Vi: Resetting IOMMU command buffer\n"); + if (iommu->reset_in_progress) + panic("AMD-Vi: ILLEGAL_COMMAND_ERROR while resetting command buffer\n"); + + iommu->reset_in_progress = true; + amd_iommu_reset_cmd_buffer(iommu); flush_all_devices_for_iommu(iommu); flush_all_domains_on_iommu(iommu); + + iommu->reset_in_progress = false; } /**************************************************************************** -- cgit v1.2.3-70-g09d2 From 6a1eddd2f951656a6abbd42e2cddc2267c4a639d Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Thu, 3 Sep 2009 15:15:10 +0200 Subject: x86/amd-iommu: Reset command buffer if wait loop fails Instead of a panic on an comletion wait loop failure, try to recover from that event from resetting the command buffer. Signed-off-by: Joerg Roedel --- arch/x86/kernel/amd_iommu.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'arch/x86/kernel') diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c index b62a2f64dfc..cfca80bfe75 100644 --- a/arch/x86/kernel/amd_iommu.c +++ b/arch/x86/kernel/amd_iommu.c @@ -318,8 +318,11 @@ static void __iommu_wait_for_completion(struct amd_iommu *iommu) status &= ~MMIO_STATUS_COM_WAIT_INT_MASK; writel(status, iommu->mmio_base + MMIO_STATUS_OFFSET); - if (unlikely(i == EXIT_LOOP_COUNT)) - panic("AMD IOMMU: Completion wait loop failed\n"); + if (unlikely(i == EXIT_LOOP_COUNT)) { + spin_unlock(&iommu->lock); + reset_iommu_command_buffer(iommu); + spin_lock(&iommu->lock); + } } /* -- cgit v1.2.3-70-g09d2