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x86/PCI: Revert "x86/PCI: Clip only host bridge windows for E820 regions"

This reverts commit 4c5e242d3e93. Prior to 4c5e242d3e93 ("x86/PCI: Clip only host bridge windows for E820 regions"), E820 regions did not affect PCI host bridge windows. We only looked at E820 regions and avoided them when allocating new MMIO space. If firmware PCI bridge window and BAR assignments used E820 regions, we left them alone. After 4c5e242d3e93, we removed E820 regions from the PCI host bridge windows before looking at BARs, so firmware assignments in E820 regions looked like errors, and we moved things around to fit in the space left (if any) after removing the E820 regions. This unnecessary BAR reassignment broke several machines. Guilherme reported that Steam Deck fails to boot after 4c5e242d3e93. We clipped the window that contained most 32-bit BARs: BIOS-e820: [mem 0x00000000a0000000-0x00000000a00fffff] reserved acpi PNP0A08:00: clipped [mem 0x80000000-0xf7ffffff window] to [mem 0xa0100000-0xf7ffffff window] for e820 entry [mem 0xa0000000-0xa00fffff] which forced us to reassign all those BARs, for example, this NVMe BAR: pci 0000:00:01.2: PCI bridge to [bus 01] pci 0000:00:01.2: bridge window [mem 0x80600000-0x806fffff] pci 0000:01:00.0: BAR 0: [mem 0x80600000-0x80603fff 64bit] pci 0000:00:01.2: can't claim window [mem 0x80600000-0x806fffff]: no compatible bridge window pci 0000:01:00.0: can't claim BAR 0 [mem 0x80600000-0x80603fff 64bit]: no compatible bridge window pci 0000:00:01.2: bridge window: assigned [mem 0xa0100000-0xa01fffff] pci 0000:01:00.0: BAR 0: assigned [mem 0xa0100000-0xa0103fff 64bit] All the reassignments were successful, so the devices should have been functional at the new addresses, but some were not. Andy reported a similar failure on an Intel MID platform. Benjamin reported a similar failure on a VMWare Fusion VM. Note: this is not a clean revert; this revert keeps the later change to make the clipping dependent on a new pci_use_e820 bool, moving the checking of this bool to arch_remove_reservations(). [bhelgaas: commit log, add more reporters and testers] BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=216109 Reported-by: Guilherme G. Piccoli <gpiccoli@igalia.com> Reported-by: Andy Shevchenko <andy.shevchenko@gmail.com> Reported-by: Benjamin Coddington <bcodding@redhat.com> Reported-by: Jongman Heo <jongman.heo@gmail.com> Fixes: 4c5e242d3e93 ("x86/PCI: Clip only host bridge windows for E820 regions") Link: https://lore.kernel.org/r/20220612144325.85366-1-hdegoede@redhat.com Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com> Tested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Tested-by: Benjamin Coddington <bcodding@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

Hans de Goede committed 4 years ago

Commit a2b36ff1 parent f2906aa4 files · +18 −17Browse files

Unified · Split

4 files
  1. arch/x86/include/asm/e820/api.h +0 −5
  2. arch/x86/include/asm/pci_x86.h +8 −0
  3. arch/x86/kernel/resource.c +9 −5
  4. arch/x86/pci/acpi.c +1 −7
arch/x86/include/asm/e820/api.h+0−5
@@ -4,9 +4,6 @@ · 3 unmodified lines
44
55 #include <asm/e820/types.h>
66
7−struct device;
8−struct resource;
9−
107 extern struct e820_table *e820_table;
118 extern struct e820_table *e820_table_kexec;
129 extern struct e820_table *e820_table_firmware;
@@ -46,8 +43,6 @@ extern void e820__register_nosave_regions(unsigned long limit_pfn); · 33 unmodified lines
4643
4744 extern int e820__get_entry_type(u64 start, u64 end);
4845
49−extern void remove_e820_regions(struct device *dev, struct resource *avail);
50−
5146 /*
5247 * Returns true iff the specified range [start,end) is completely contained inside
5348 * the ISA region.
arch/x86/include/asm/pci_x86.h+8−0
@@ -69,6 +69,8 @@ void pcibios_scan_specific_bus(int busn); · 68 unmodified lines
6969
7070 /* pci-irq.c */
7171
72+struct pci_dev;
73+
7274 struct irq_info {
7375 u8 bus, devfn; /* Bus, device and function */
7476 struct {
@@ -246,3 +248,9 @@ static inline void mmio_config_writel(void __iomem *pos, u32 val) · 171 unmodified lines
246248 # define x86_default_pci_init_irq NULL
247249 # define x86_default_pci_fixup_irqs NULL
248250 #endif
251+
252+#if defined(CONFIG_PCI) && defined(CONFIG_ACPI)
253+extern bool pci_use_e820;
254+#else
255+#define pci_use_e820 false
256+#endif
arch/x86/kernel/resource.c+9−5
@@ -1,7 +1,8 @@
11 // SPDX-License-Identifier: GPL-2.0
2−#include <linux/dev_printk.h>
32 #include <linux/ioport.h>
3+#include <linux/printk.h>
44 #include <asm/e820/api.h>
5+#include <asm/pci_x86.h>
56
67 static void resource_clip(struct resource *res, resource_size_t start,
78 resource_size_t end)
@@ -24,14 +25,14 @@ static void resource_clip(struct resource *res, resource_size_t start, · 16 unmodified lines
2425 res->start = end + 1;
2526 }
2627
27−void remove_e820_regions(struct device *dev, struct resource *avail)
28+static void remove_e820_regions(struct resource *avail)
2829 {
2930 int i;
3031 struct e820_entry *entry;
3132 u64 e820_start, e820_end;
3233 struct resource orig = *avail;
3334
34− if (!(avail->flags & IORESOURCE_MEM))
35+ if (!pci_use_e820)
3536 return;
3637
3738 for (i = 0; i < e820_table->nr_entries; i++) {
@@ -41,7 +42,7 @@ void remove_e820_regions(struct device *dev, struct resource *avail) · 3 unmodified lines
4142
4243 resource_clip(avail, e820_start, e820_end);
4344 if (orig.start != avail->start || orig.end != avail->end) {
44− dev_info(dev, "clipped %pR to %pR for e820 entry [mem %#010Lx-%#010Lx]\n",
45+ pr_info("clipped %pR to %pR for e820 entry [mem %#010Lx-%#010Lx]\n",
4546 &orig, avail, e820_start, e820_end);
4647 orig = *avail;
4748 }
@@ -55,6 +56,9 @@ void arch_remove_reservations(struct resource *avail) · 7 unmodified lines
5556 * the low 1MB unconditionally, as this area is needed for some ISA
5657 * cards requiring a memory range, e.g. the i82365 PCMCIA controller.
5758 */
58− if (avail->flags & IORESOURCE_MEM)
59+ if (avail->flags & IORESOURCE_MEM) {
5960 resource_clip(avail, BIOS_ROM_BASE, BIOS_ROM_END);
61+
62+ remove_e820_regions(avail);
63+ }
6064 }
arch/x86/pci/acpi.c+1−7
@@ -8,7 +8,6 @@ · 7 unmodified lines
88 #include <linux/pci-acpi.h>
99 #include <asm/numa.h>
1010 #include <asm/pci_x86.h>
11−#include <asm/e820/api.h>
1211
1312 struct pci_root_info {
1413 struct acpi_pci_root_info common;
@@ -20,7 +19,7 @@ struct pci_root_info { · 5 unmodified lines
2019 #endif
2120 };
2221
23−static bool pci_use_e820 = true;
22+bool pci_use_e820 = true;
2423 static bool pci_use_crs = true;
2524 static bool pci_ignore_seg;
2625
@@ -387,11 +386,6 @@ static int pci_acpi_root_prepare_resources(struct acpi_pci_root_info *ci) · 360 unmodified lines
387386
388387 status = acpi_pci_probe_root_resources(ci);
389388
390− if (pci_use_e820) {
391− resource_list_for_each_entry(entry, &ci->resources)
392− remove_e820_regions(&device->dev, entry->res);
393− }
394−
395389 if (pci_use_crs) {
396390 resource_list_for_each_entry_safe(entry, tmp, &ci->resources)
397391 if (resource_is_pcicfg_ioport(entry->res))