From b1a504a6500df50e83b701b7946b34fce27ad8a3 Mon Sep 17 00:00:00 2001 From: Cédric Le Goater Date: Fri, 6 Mar 2020 16:01:40 +0100 Subject: powerpc/xive: Use XIVE_BAD_IRQ instead of zero to catch non configured IPIs MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit When a CPU is brought up, an IPI number is allocated and recorded under the XIVE CPU structure. Invalid IPI numbers are tracked with interrupt number 0x0. On the PowerNV platform, the interrupt number space starts at 0x10 and this works fine. However, on the sPAPR platform, it is possible to allocate the interrupt number 0x0 and this raises an issue when CPU 0 is unplugged. The XIVE spapr driver tracks allocated interrupt numbers in a bitmask and it is not correctly updated when interrupt number 0x0 is freed. It stays allocated and it is then impossible to reallocate. Fix by using the XIVE_BAD_IRQ value instead of zero on both platforms. Reported-by: David Gibson Fixes: eac1e731b59e ("powerpc/xive: guest exploitation of the XIVE interrupt controller") Cc: stable@vger.kernel.org # v4.14+ Signed-off-by: Cédric Le Goater Reviewed-by: David Gibson Tested-by: David Gibson Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200306150143.5551-2-clg@kaod.org --- arch/powerpc/sysdev/xive/native.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'arch/powerpc/sysdev/xive/native.c') diff --git a/arch/powerpc/sysdev/xive/native.c b/arch/powerpc/sysdev/xive/native.c index 0ff6b739052c..50e1a8e02497 100644 --- a/arch/powerpc/sysdev/xive/native.c +++ b/arch/powerpc/sysdev/xive/native.c @@ -312,7 +312,7 @@ static void xive_native_put_ipi(unsigned int cpu, struct xive_cpu *xc) s64 rc; /* Free the IPI */ - if (!xc->hw_ipi) + if (xc->hw_ipi == XIVE_BAD_IRQ) return; for (;;) { rc = opal_xive_free_irq(xc->hw_ipi); @@ -320,7 +320,7 @@ static void xive_native_put_ipi(unsigned int cpu, struct xive_cpu *xc) msleep(OPAL_BUSY_DELAY_MS); continue; } - xc->hw_ipi = 0; + xc->hw_ipi = XIVE_BAD_IRQ; break; } } -- cgit v1.2.3 From 930914b7d528fc6b0249bffc00564100bcf6ef75 Mon Sep 17 00:00:00 2001 From: Cédric Le Goater Date: Fri, 6 Mar 2020 16:01:43 +0100 Subject: powerpc/xive: Add a debugfs file to dump internal XIVE state MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit As does XMON, the debugfs file /sys/kernel/debug/powerpc/xive exposes the XIVE internal state of the machine CPUs and interrupts. Available on the PowerNV and sPAPR platforms. Signed-off-by: Cédric Le Goater [mpe: Make the debugfs file 0400] Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200306150143.5551-5-clg@kaod.org --- arch/powerpc/sysdev/xive/common.c | 105 +++++++++++++++++++++++++++++++ arch/powerpc/sysdev/xive/native.c | 3 + arch/powerpc/sysdev/xive/spapr.c | 19 ++++++ arch/powerpc/sysdev/xive/xive-internal.h | 2 + 4 files changed, 129 insertions(+) (limited to 'arch/powerpc/sysdev/xive/native.c') diff --git a/arch/powerpc/sysdev/xive/common.c b/arch/powerpc/sysdev/xive/common.c index 0a47ddf3c148..b294f70f1a67 100644 --- a/arch/powerpc/sysdev/xive/common.c +++ b/arch/powerpc/sysdev/xive/common.c @@ -20,6 +20,7 @@ #include #include +#include #include #include #include @@ -1555,3 +1556,107 @@ static int __init xive_off(char *arg) return 0; } __setup("xive=off", xive_off); + +void xive_debug_show_cpu(struct seq_file *m, int cpu) +{ + struct xive_cpu *xc = per_cpu(xive_cpu, cpu); + + seq_printf(m, "CPU %d:", cpu); + if (xc) { + seq_printf(m, "pp=%02x CPPR=%02x ", xc->pending_prio, xc->cppr); + +#ifdef CONFIG_SMP + { + u64 val = xive_esb_read(&xc->ipi_data, XIVE_ESB_GET); + + seq_printf(m, "IPI=0x%08x PQ=%c%c ", xc->hw_ipi, + val & XIVE_ESB_VAL_P ? 'P' : '-', + val & XIVE_ESB_VAL_Q ? 'Q' : '-'); + } +#endif + { + struct xive_q *q = &xc->queue[xive_irq_priority]; + u32 i0, i1, idx; + + if (q->qpage) { + idx = q->idx; + i0 = be32_to_cpup(q->qpage + idx); + idx = (idx + 1) & q->msk; + i1 = be32_to_cpup(q->qpage + idx); + seq_printf(m, "EQ idx=%d T=%d %08x %08x ...", + q->idx, q->toggle, i0, i1); + } + } + } + seq_puts(m, "\n"); +} + +void xive_debug_show_irq(struct seq_file *m, u32 hw_irq, struct irq_data *d) +{ + struct irq_chip *chip = irq_data_get_irq_chip(d); + int rc; + u32 target; + u8 prio; + u32 lirq; + + if (!is_xive_irq(chip)) + return; + + rc = xive_ops->get_irq_config(hw_irq, &target, &prio, &lirq); + if (rc) { + seq_printf(m, "IRQ 0x%08x : no config rc=%d\n", hw_irq, rc); + return; + } + + seq_printf(m, "IRQ 0x%08x : target=0x%x prio=%02x lirq=0x%x ", + hw_irq, target, prio, lirq); + + if (d) { + struct xive_irq_data *xd = irq_data_get_irq_handler_data(d); + u64 val = xive_esb_read(xd, XIVE_ESB_GET); + + seq_printf(m, "flags=%c%c%c PQ=%c%c", + xd->flags & XIVE_IRQ_FLAG_STORE_EOI ? 'S' : ' ', + xd->flags & XIVE_IRQ_FLAG_LSI ? 'L' : ' ', + xd->flags & XIVE_IRQ_FLAG_H_INT_ESB ? 'H' : ' ', + val & XIVE_ESB_VAL_P ? 'P' : '-', + val & XIVE_ESB_VAL_Q ? 'Q' : '-'); + } + seq_puts(m, "\n"); +} + +static int xive_core_debug_show(struct seq_file *m, void *private) +{ + unsigned int i; + struct irq_desc *desc; + int cpu; + + if (xive_ops->debug_show) + xive_ops->debug_show(m, private); + + for_each_possible_cpu(cpu) + xive_debug_show_cpu(m, cpu); + + for_each_irq_desc(i, desc) { + struct irq_data *d = irq_desc_get_irq_data(desc); + unsigned int hw_irq; + + if (!d) + continue; + + hw_irq = (unsigned int)irqd_to_hwirq(d); + + /* IPIs are special (HW number 0) */ + if (hw_irq) + xive_debug_show_irq(m, hw_irq, d); + } + return 0; +} +DEFINE_SHOW_ATTRIBUTE(xive_core_debug); + +int xive_core_debug_init(void) +{ + debugfs_create_file("xive", 0400, powerpc_debugfs_root, + NULL, &xive_core_debug_fops); + return 0; +} diff --git a/arch/powerpc/sysdev/xive/native.c b/arch/powerpc/sysdev/xive/native.c index 50e1a8e02497..5218fdc4b29a 100644 --- a/arch/powerpc/sysdev/xive/native.c +++ b/arch/powerpc/sysdev/xive/native.c @@ -19,6 +19,7 @@ #include #include +#include #include #include #include @@ -850,3 +851,5 @@ int xive_native_get_vp_state(u32 vp_id, u64 *out_state) return 0; } EXPORT_SYMBOL_GPL(xive_native_get_vp_state); + +machine_arch_initcall(powernv, xive_core_debug_init); diff --git a/arch/powerpc/sysdev/xive/spapr.c b/arch/powerpc/sysdev/xive/spapr.c index 3f15615712b5..7ab5c6780997 100644 --- a/arch/powerpc/sysdev/xive/spapr.c +++ b/arch/powerpc/sysdev/xive/spapr.c @@ -18,6 +18,7 @@ #include #include +#include #include #include #include @@ -645,6 +646,21 @@ static void xive_spapr_sync_source(u32 hw_irq) plpar_int_sync(0, hw_irq); } +static int xive_spapr_debug_show(struct seq_file *m, void *private) +{ + struct xive_irq_bitmap *xibm; + char *buf = kmalloc(PAGE_SIZE, GFP_KERNEL); + + list_for_each_entry(xibm, &xive_irq_bitmaps, list) { + memset(buf, 0, PAGE_SIZE); + bitmap_print_to_pagebuf(true, buf, xibm->bitmap, xibm->count); + seq_printf(m, "bitmap #%d: %s", xibm->count, buf); + } + kfree(buf); + + return 0; +} + static const struct xive_ops xive_spapr_ops = { .populate_irq_data = xive_spapr_populate_irq_data, .configure_irq = xive_spapr_configure_irq, @@ -662,6 +678,7 @@ static const struct xive_ops xive_spapr_ops = { #ifdef CONFIG_SMP .get_ipi = xive_spapr_get_ipi, .put_ipi = xive_spapr_put_ipi, + .debug_show = xive_spapr_debug_show, #endif /* CONFIG_SMP */ .name = "spapr", }; @@ -839,3 +856,5 @@ bool __init xive_spapr_init(void) pr_info("Using %dkB queues\n", 1 << (xive_queue_shift - 10)); return true; } + +machine_arch_initcall(pseries, xive_core_debug_init); diff --git a/arch/powerpc/sysdev/xive/xive-internal.h b/arch/powerpc/sysdev/xive/xive-internal.h index 382980f4de2d..b7b901da2168 100644 --- a/arch/powerpc/sysdev/xive/xive-internal.h +++ b/arch/powerpc/sysdev/xive/xive-internal.h @@ -57,12 +57,14 @@ struct xive_ops { int (*get_ipi)(unsigned int cpu, struct xive_cpu *xc); void (*put_ipi)(unsigned int cpu, struct xive_cpu *xc); #endif + int (*debug_show)(struct seq_file *m, void *private); const char *name; }; bool xive_core_init(const struct xive_ops *ops, void __iomem *area, u32 offset, u8 max_prio); __be32 *xive_queue_page_alloc(unsigned int cpu, u32 queue_shift); +int xive_core_debug_init(void); static inline u32 xive_alloc_order(u32 queue_shift) { -- cgit v1.2.3