* Re: [PATCH v2 2/4] PCI: Move jailhouse's isolated function handling to pci_scan_slot()
@ 2022-04-13 22:12 kernel test robot
0 siblings, 0 replies; 6+ messages in thread
From: kernel test robot @ 2022-04-13 22:12 UTC (permalink / raw)
To: kbuild
[-- Attachment #1: Type: text/plain, Size: 31912 bytes --]
CC: llvm(a)lists.linux.dev
CC: kbuild-all(a)lists.01.org
BCC: lkp(a)intel.com
In-Reply-To: <20220412143040.1882096-3-schnelle@linux.ibm.com>
References: <20220412143040.1882096-3-schnelle@linux.ibm.com>
TO: Niklas Schnelle <schnelle@linux.ibm.com>
TO: Bjorn Helgaas <helgaas@kernel.org>
TO: Jan Kiszka <jan.kiszka@siemens.com>
TO: Matthew Rosato <mjrosato@linux.ibm.com>
TO: Pierre Morel <pmorel@linux.ibm.com>
CC: linux-s390(a)vger.kernel.org
CC: linux-pci(a)vger.kernel.org
Hi Niklas,
I love your patch! Perhaps something to improve:
[auto build test WARNING on helgaas-pci/next]
[also build test WARNING on s390/features tip/x86/core v5.18-rc2 next-20220413]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/intel-lab-lkp/linux/commits/Niklas-Schnelle/PCI-Rework-pci_scan_slot-and-isolated-PCI-functions/20220412-223307
base: https://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci.git next
:::::: branch date: 32 hours ago
:::::: commit date: 32 hours ago
config: x86_64-randconfig-c007-20220411 (https://download.01.org/0day-ci/archive/20220414/202204140641.r3fD3EBW-lkp(a)intel.com/config)
compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project fe2478d44e4f7f191c43fef629ac7a23d0251e72)
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/intel-lab-lkp/linux/commit/5cac6729750b7434ff5d6ae99469e9e54bc9fb6e
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review Niklas-Schnelle/PCI-Rework-pci_scan_slot-and-isolated-PCI-functions/20220412-223307
git checkout 5cac6729750b7434ff5d6ae99469e9e54bc9fb6e
# save the config file to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64 clang-analyzer
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
clang-analyzer warnings: (new ones prefixed by >>)
if (primary & WM831X_TCHDATA_INT)
^
drivers/mfd/wm831x-irq.c:478:2: note: Loop condition is true. Entering loop body
for (i = 0; i < ARRAY_SIZE(wm831x_irqs); i++) {
^
drivers/mfd/wm831x-irq.c:481:7: note: Assuming the condition is false
if (!(primary & wm831x_irqs[i].primary))
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/mfd/wm831x-irq.c:481:3: note: Taking false branch
if (!(primary & wm831x_irqs[i].primary))
^
drivers/mfd/wm831x-irq.c:488:7: note: Assuming the condition is false
if (!read[offset]) {
^~~~~~~~~~~~~
drivers/mfd/wm831x-irq.c:488:3: note: Taking false branch
if (!read[offset]) {
^
drivers/mfd/wm831x-irq.c:510:7: note: Assuming the condition is false
if (*status & wm831x_irqs[i].mask)
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/mfd/wm831x-irq.c:510:3: note: Taking false branch
if (*status & wm831x_irqs[i].mask)
^
drivers/mfd/wm831x-irq.c:517:7: note: Assuming 'primary' is equal to WM831X_GP_INT
if (primary == WM831X_GP_INT &&
^~~~~~~~~~~~~~~~~~~~~~~~
drivers/mfd/wm831x-irq.c:517:7: note: Left side of '&&' is true
drivers/mfd/wm831x-irq.c:518:7: note: Assuming the condition is false
wm831x->gpio_level_high[i - WM831X_IRQ_GPIO_1]) {
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/mfd/wm831x-irq.c:517:3: note: Taking false branch
if (primary == WM831X_GP_INT &&
^
drivers/mfd/wm831x-irq.c:528:7: note: 'primary' is equal to WM831X_GP_INT
if (primary == WM831X_GP_INT &&
^~~~~~~
drivers/mfd/wm831x-irq.c:528:7: note: Left side of '&&' is true
drivers/mfd/wm831x-irq.c:529:7: note: Assuming the condition is true
wm831x->gpio_level_low[i - WM831X_IRQ_GPIO_1]) {
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/mfd/wm831x-irq.c:528:3: note: Taking true branch
if (primary == WM831X_GP_INT &&
^
drivers/mfd/wm831x-irq.c:531:21: note: The result of the left shift is undefined due to shifting by '4294967295', which is greater or equal to the width of type 'int'
while (!(ret & 1 << (i - WM831X_IRQ_GPIO_1))) {
^ ~~~~~~~~~~~~~~~~~~~~~~~
Suppressed 41 warnings (41 in non-user code).
Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
47 warnings generated.
block/partitions/cmdline.c:84:3: warning: Call to function 'strncpy' is insecure as it does not provide security checks introduced in the C11 standard. Replace with analogous functions that support length arguments or provides boundary checks such as 'strncpy_s' in case of C11 [clang-analyzer-security.insecureAPI.DeprecatedOrUnsafeBufferHandling]
strncpy(new_subpart->name, partdef, length);
^~~~~~~
block/partitions/cmdline.c:84:3: note: Call to function 'strncpy' is insecure as it does not provide security checks introduced in the C11 standard. Replace with analogous functions that support length arguments or provides boundary checks such as 'strncpy_s' in case of C11
strncpy(new_subpart->name, partdef, length);
^~~~~~~
block/partitions/cmdline.c:143:2: warning: Call to function 'strncpy' is insecure as it does not provide security checks introduced in the C11 standard. Replace with analogous functions that support length arguments or provides boundary checks such as 'strncpy_s' in case of C11 [clang-analyzer-security.insecureAPI.DeprecatedOrUnsafeBufferHandling]
strncpy(newparts->name, bdevdef, length);
^~~~~~~
block/partitions/cmdline.c:143:2: note: Call to function 'strncpy' is insecure as it does not provide security checks introduced in the C11 standard. Replace with analogous functions that support length arguments or provides boundary checks such as 'strncpy_s' in case of C11
strncpy(newparts->name, bdevdef, length);
^~~~~~~
block/partitions/cmdline.c:156:3: warning: Call to function 'strncpy' is insecure as it does not provide security checks introduced in the C11 standard. Replace with analogous functions that support length arguments or provides boundary checks such as 'strncpy_s' in case of C11 [clang-analyzer-security.insecureAPI.DeprecatedOrUnsafeBufferHandling]
strncpy(buf, bdevdef, length);
^~~~~~~
block/partitions/cmdline.c:156:3: note: Call to function 'strncpy' is insecure as it does not provide security checks introduced in the C11 standard. Replace with analogous functions that support length arguments or provides boundary checks such as 'strncpy_s' in case of C11
strncpy(buf, bdevdef, length);
^~~~~~~
block/partitions/cmdline.c:270:2: warning: Call to function 'strncpy' is insecure as it does not provide security checks introduced in the C11 standard. Replace with analogous functions that support length arguments or provides boundary checks such as 'strncpy_s' in case of C11 [clang-analyzer-security.insecureAPI.DeprecatedOrUnsafeBufferHandling]
strncpy(info->volname, subpart->name, label_min);
^~~~~~~
block/partitions/cmdline.c:270:2: note: Call to function 'strncpy' is insecure as it does not provide security checks introduced in the C11 standard. Replace with analogous functions that support length arguments or provides boundary checks such as 'strncpy_s' in case of C11
strncpy(info->volname, subpart->name, label_min);
^~~~~~~
block/partitions/cmdline.c:273:2: warning: Call to function 'snprintf' is insecure as it does not provide security checks introduced in the C11 standard. Replace with analogous functions that support length arguments or provides boundary checks such as 'snprintf_s' in case of C11 [clang-analyzer-security.insecureAPI.DeprecatedOrUnsafeBufferHandling]
snprintf(tmp, sizeof(tmp), "(%s)", info->volname);
^~~~~~~~
block/partitions/cmdline.c:273:2: note: Call to function 'snprintf' is insecure as it does not provide security checks introduced in the C11 standard. Replace with analogous functions that support length arguments or provides boundary checks such as 'snprintf_s' in case of C11
snprintf(tmp, sizeof(tmp), "(%s)", info->volname);
^~~~~~~~
Suppressed 42 warnings (42 in non-user code).
Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
33 warnings generated.
Suppressed 33 warnings (33 in non-user code).
Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
33 warnings generated.
Suppressed 33 warnings (33 in non-user code).
Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
37 warnings generated.
drivers/pci/probe.c:1013:4: warning: Call to function 'snprintf' is insecure as it does not provide security checks introduced in the C11 standard. Replace with analogous functions that support length arguments or provides boundary checks such as 'snprintf_s' in case of C11 [clang-analyzer-security.insecureAPI.DeprecatedOrUnsafeBufferHandling]
snprintf(addr, sizeof(addr), fmt,
^~~~~~~~
drivers/pci/probe.c:1013:4: note: Call to function 'snprintf' is insecure as it does not provide security checks introduced in the C11 standard. Replace with analogous functions that support length arguments or provides boundary checks such as 'snprintf_s' in case of C11
snprintf(addr, sizeof(addr), fmt,
^~~~~~~~
drivers/pci/probe.c:1447:2: warning: Call to function 'sprintf' is insecure as it does not provide bounding of the memory buffer or security checks introduced in the C11 standard. Replace with analogous functions that support length arguments or provides boundary checks such as 'sprintf_s' in case of C11 [clang-analyzer-security.insecureAPI.DeprecatedOrUnsafeBufferHandling]
sprintf(child->name,
^~~~~~~
drivers/pci/probe.c:1447:2: note: Call to function 'sprintf' is insecure as it does not provide bounding of the memory buffer or security checks introduced in the C11 standard. Replace with analogous functions that support length arguments or provides boundary checks such as 'sprintf_s' in case of C11
sprintf(child->name,
^~~~~~~
>> drivers/pci/probe.c:2867:3: warning: Value stored to 'nr_devs' is never read [clang-analyzer-deadcode.DeadStores]
nr_devs = pci_scan_slot(bus, devfn);
^ ~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/pci/probe.c:2867:3: note: Value stored to 'nr_devs' is never read
nr_devs = pci_scan_slot(bus, devfn);
^ ~~~~~~~~~~~~~~~~~~~~~~~~~
Suppressed 34 warnings (33 in non-user code, 1 with check filters).
Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
33 warnings generated.
Suppressed 33 warnings (33 in non-user code).
Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
33 warnings generated.
Suppressed 33 warnings (33 in non-user code).
Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
44 warnings generated.
drivers/pci/pci.c:286:9: warning: Call to function 'sscanf' is insecure as it does not provide security checks introduced in the C11 standard. Replace with analogous functions that support length arguments or provides boundary checks such as 'sscanf_s' in case of C11 [clang-analyzer-security.insecureAPI.DeprecatedOrUnsafeBufferHandling]
ret = sscanf(p, "/%x.%x%c", &slot, &func, &end);
^~~~~~
drivers/pci/pci.c:286:9: note: Call to function 'sscanf' is insecure as it does not provide security checks introduced in the C11 standard. Replace with analogous functions that support length arguments or provides boundary checks such as 'sscanf_s' in case of C11
ret = sscanf(p, "/%x.%x%c", &slot, &func, &end);
^~~~~~
drivers/pci/pci.c:312:8: warning: Call to function 'sscanf' is insecure as it does not provide security checks introduced in the C11 standard. Replace with analogous functions that support length arguments or provides boundary checks such as 'sscanf_s' in case of C11 [clang-analyzer-security.insecureAPI.DeprecatedOrUnsafeBufferHandling]
ret = sscanf(wpath, "%x:%x:%x.%x%c", &seg, &bus, &slot,
^~~~~~
drivers/pci/pci.c:312:8: note: Call to function 'sscanf' is insecure as it does not provide security checks introduced in the C11 standard. Replace with analogous functions that support length arguments or provides boundary checks such as 'sscanf_s' in case of C11
ret = sscanf(wpath, "%x:%x:%x.%x%c", &seg, &bus, &slot,
^~~~~~
drivers/pci/pci.c:316:9: warning: Call to function 'sscanf' is insecure as it does not provide security checks introduced in the C11 standard. Replace with analogous functions that support length arguments or provides boundary checks such as 'sscanf_s' in case of C11 [clang-analyzer-security.insecureAPI.DeprecatedOrUnsafeBufferHandling]
ret = sscanf(wpath, "%x:%x.%x%c", &bus, &slot, &func, &end);
^~~~~~
drivers/pci/pci.c:316:9: note: Call to function 'sscanf' is insecure as it does not provide security checks introduced in the C11 standard. Replace with analogous functions that support length arguments or provides boundary checks such as 'sscanf_s' in case of C11
ret = sscanf(wpath, "%x:%x.%x%c", &bus, &slot, &func, &end);
^~~~~~
drivers/pci/pci.c:372:9: warning: Call to function 'sscanf' is insecure as it does not provide security checks introduced in the C11 standard. Replace with analogous functions that support length arguments or provides boundary checks such as 'sscanf_s' in case of C11 [clang-analyzer-security.insecureAPI.DeprecatedOrUnsafeBufferHandling]
ret = sscanf(p, "%hx:%hx:%hx:%hx%n", &vendor, &device,
^~~~~~
drivers/pci/pci.c:372:9: note: Call to function 'sscanf' is insecure as it does not provide security checks introduced in the C11 standard. Replace with analogous functions that support length arguments or provides boundary checks such as 'sscanf_s' in case of C11
ret = sscanf(p, "%hx:%hx:%hx:%hx%n", &vendor, &device,
^~~~~~
drivers/pci/pci.c:375:10: warning: Call to function 'sscanf' is insecure as it does not provide security checks introduced in the C11 standard. Replace with analogous functions that support length arguments or provides boundary checks such as 'sscanf_s' in case of C11 [clang-analyzer-security.insecureAPI.DeprecatedOrUnsafeBufferHandling]
ret = sscanf(p, "%hx:%hx%n", &vendor, &device, &count);
^~~~~~
drivers/pci/pci.c:375:10: note: Call to function 'sscanf' is insecure as it does not provide security checks introduced in the C11 standard. Replace with analogous functions that support length arguments or provides boundary checks such as 'sscanf_s' in case of C11
ret = sscanf(p, "%hx:%hx%n", &vendor, &device, &count);
^~~~~~
drivers/pci/pci.c:1783:2: warning: Call to function 'memcpy' is insecure as it does not provide security checks introduced in the C11 standard. Replace with analogous functions that support length arguments or provides boundary checks such as 'memcpy_s' in case of C11 [clang-analyzer-security.insecureAPI.DeprecatedOrUnsafeBufferHandling]
memcpy(state->config_space, dev->saved_config_space,
^
include/linux/fortify-string.h:369:26: note: expanded from macro 'memcpy'
#define memcpy(p, q, s) __fortify_memcpy_chk(p, q, s, \
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/fortify-string.h:362:2: note: expanded from macro '__fortify_memcpy_chk'
__underlying_##op(p, q, __fortify_size); \
^~~~~~~~~~~~~~~~~
note: expanded from here
include/linux/fortify-string.h:45:29: note: expanded from macro '__underlying_memcpy'
#define __underlying_memcpy __builtin_memcpy
^~~~~~~~~~~~~~~~
drivers/pci/pci.c:1783:2: note: Call to function 'memcpy' is insecure as it does not provide security checks introduced in the C11 standard. Replace with analogous functions that support length arguments or provides boundary checks such as 'memcpy_s' in case of C11
memcpy(state->config_space, dev->saved_config_space,
^
include/linux/fortify-string.h:369:26: note: expanded from macro 'memcpy'
#define memcpy(p, q, s) __fortify_memcpy_chk(p, q, s, \
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/fortify-string.h:362:2: note: expanded from macro '__fortify_memcpy_chk'
__underlying_##op(p, q, __fortify_size); \
^~~~~~~~~~~~~~~~~
note: expanded from here
include/linux/fortify-string.h:45:29: note: expanded from macro '__underlying_memcpy'
#define __underlying_memcpy __builtin_memcpy
^~~~~~~~~~~~~~~~
drivers/pci/pci.c:1789:3: warning: Call to function 'memcpy' is insecure as it does not provide security checks introduced in the C11 standard. Replace with analogous functions that support length arguments or provides boundary checks such as 'memcpy_s' in case of C11 [clang-analyzer-security.insecureAPI.DeprecatedOrUnsafeBufferHandling]
memcpy(cap, &tmp->cap, len);
^
include/linux/fortify-string.h:369:26: note: expanded from macro 'memcpy'
#define memcpy(p, q, s) __fortify_memcpy_chk(p, q, s, \
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/fortify-string.h:362:2: note: expanded from macro '__fortify_memcpy_chk'
__underlying_##op(p, q, __fortify_size); \
^~~~~~~~~~~~~~~~~
note: expanded from here
include/linux/fortify-string.h:45:29: note: expanded from macro '__underlying_memcpy'
#define __underlying_memcpy __builtin_memcpy
^~~~~~~~~~~~~~~~
drivers/pci/pci.c:1789:3: note: Call to function 'memcpy' is insecure as it does not provide security checks introduced in the C11 standard. Replace with analogous functions that support length arguments or provides boundary checks such as 'memcpy_s' in case of C11
memcpy(cap, &tmp->cap, len);
^
include/linux/fortify-string.h:369:26: note: expanded from macro 'memcpy'
#define memcpy(p, q, s) __fortify_memcpy_chk(p, q, s, \
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/fortify-string.h:362:2: note: expanded from macro '__fortify_memcpy_chk'
__underlying_##op(p, q, __fortify_size); \
^~~~~~~~~~~~~~~~~
note: expanded from here
include/linux/fortify-string.h:45:29: note: expanded from macro '__underlying_memcpy'
#define __underlying_memcpy __builtin_memcpy
^~~~~~~~~~~~~~~~
drivers/pci/pci.c:1813:2: warning: Call to function 'memcpy' is insecure as it does not provide security checks introduced in the C11 standard. Replace with analogous functions that support length arguments or provides boundary checks such as 'memcpy_s' in case of C11 [clang-analyzer-security.insecureAPI.DeprecatedOrUnsafeBufferHandling]
memcpy(dev->saved_config_space, state->config_space,
^
include/linux/fortify-string.h:369:26: note: expanded from macro 'memcpy'
vim +/nr_devs +2867 drivers/pci/probe.c
bccf90d6e063d27 Palmer Dabbelt 2017-06-23 2841
1c02ea81006548a Mika Westerberg 2017-10-13 2842 /**
1c02ea81006548a Mika Westerberg 2017-10-13 2843 * pci_scan_child_bus_extend() - Scan devices below a bus
1c02ea81006548a Mika Westerberg 2017-10-13 2844 * @bus: Bus to scan for devices
1c02ea81006548a Mika Westerberg 2017-10-13 2845 * @available_buses: Total number of buses available (%0 does not try to
1c02ea81006548a Mika Westerberg 2017-10-13 2846 * extend beyond the minimal)
1c02ea81006548a Mika Westerberg 2017-10-13 2847 *
1c02ea81006548a Mika Westerberg 2017-10-13 2848 * Scans devices below @bus including subordinate buses. Returns new
1c02ea81006548a Mika Westerberg 2017-10-13 2849 * subordinate number including all the found devices. Passing
1c02ea81006548a Mika Westerberg 2017-10-13 2850 * @available_buses causes the remaining bus space to be distributed
1c02ea81006548a Mika Westerberg 2017-10-13 2851 * equally between hotplug-capable bridges to allow future extension of the
1c02ea81006548a Mika Westerberg 2017-10-13 2852 * hierarchy.
1c02ea81006548a Mika Westerberg 2017-10-13 2853 */
1c02ea81006548a Mika Westerberg 2017-10-13 2854 static unsigned int pci_scan_child_bus_extend(struct pci_bus *bus,
1c02ea81006548a Mika Westerberg 2017-10-13 2855 unsigned int available_buses)
1c02ea81006548a Mika Westerberg 2017-10-13 2856 {
1c02ea81006548a Mika Westerberg 2017-10-13 2857 unsigned int used_buses, normal_bridges = 0, hotplug_bridges = 0;
1c02ea81006548a Mika Westerberg 2017-10-13 2858 unsigned int start = bus->busn_res.start;
5cac6729750b743 Niklas Schnelle 2022-04-12 2859 unsigned int devfn, cmax, max = start;
^1da177e4c3f415 Linus Torvalds 2005-04-16 2860 struct pci_dev *dev;
690f4304104f37e Jan Kiszka 2018-03-07 2861 int nr_devs;
^1da177e4c3f415 Linus Torvalds 2005-04-16 2862
0207c356ef0e2ba Bjorn Helgaas 2009-11-04 2863 dev_dbg(&bus->dev, "scanning bus\n");
^1da177e4c3f415 Linus Torvalds 2005-04-16 2864
^1da177e4c3f415 Linus Torvalds 2005-04-16 2865 /* Go find them, Rover! */
5cac6729750b743 Niklas Schnelle 2022-04-12 2866 for (devfn = 0; devfn < 256; devfn += 8)
690f4304104f37e Jan Kiszka 2018-03-07 @2867 nr_devs = pci_scan_slot(bus, devfn);
690f4304104f37e Jan Kiszka 2018-03-07 2868
3e466e2d3a04c72 Bjorn Helgaas 2017-11-30 2869 /* Reserve buses for SR-IOV capability */
1c02ea81006548a Mika Westerberg 2017-10-13 2870 used_buses = pci_iov_bus_range(bus);
1c02ea81006548a Mika Westerberg 2017-10-13 2871 max += used_buses;
a28724b0fb909d2 Yu Zhao 2009-03-20 2872
^1da177e4c3f415 Linus Torvalds 2005-04-16 2873 /*
^1da177e4c3f415 Linus Torvalds 2005-04-16 2874 * After performing arch-dependent fixup of the bus, look behind
^1da177e4c3f415 Linus Torvalds 2005-04-16 2875 * all PCI-to-PCI bridges on this bus.
^1da177e4c3f415 Linus Torvalds 2005-04-16 2876 */
74710ded8e16fc8 Alex Chiang 2009-03-20 2877 if (!bus->is_added) {
0207c356ef0e2ba Bjorn Helgaas 2009-11-04 2878 dev_dbg(&bus->dev, "fixups for bus\n");
^1da177e4c3f415 Linus Torvalds 2005-04-16 2879 pcibios_fixup_bus(bus);
74710ded8e16fc8 Alex Chiang 2009-03-20 2880 bus->is_added = 1;
74710ded8e16fc8 Alex Chiang 2009-03-20 2881 }
74710ded8e16fc8 Alex Chiang 2009-03-20 2882
1c02ea81006548a Mika Westerberg 2017-10-13 2883 /*
1c02ea81006548a Mika Westerberg 2017-10-13 2884 * Calculate how many hotplug bridges and normal bridges there
1c02ea81006548a Mika Westerberg 2017-10-13 2885 * are on this bus. We will distribute the additional available
1c02ea81006548a Mika Westerberg 2017-10-13 2886 * buses between hotplug bridges.
1c02ea81006548a Mika Westerberg 2017-10-13 2887 */
1c02ea81006548a Mika Westerberg 2017-10-13 2888 for_each_pci_bridge(dev, bus) {
1c02ea81006548a Mika Westerberg 2017-10-13 2889 if (dev->is_hotplug_bridge)
1c02ea81006548a Mika Westerberg 2017-10-13 2890 hotplug_bridges++;
1c02ea81006548a Mika Westerberg 2017-10-13 2891 else
1c02ea81006548a Mika Westerberg 2017-10-13 2892 normal_bridges++;
1c02ea81006548a Mika Westerberg 2017-10-13 2893 }
1c02ea81006548a Mika Westerberg 2017-10-13 2894
4147c2fd9b12ae1 Mika Westerberg 2017-10-13 2895 /*
4147c2fd9b12ae1 Mika Westerberg 2017-10-13 2896 * Scan bridges that are already configured. We don't touch them
4147c2fd9b12ae1 Mika Westerberg 2017-10-13 2897 * unless they are misconfigured (which will be done in the second
4147c2fd9b12ae1 Mika Westerberg 2017-10-13 2898 * scan below).
4147c2fd9b12ae1 Mika Westerberg 2017-10-13 2899 */
1c02ea81006548a Mika Westerberg 2017-10-13 2900 for_each_pci_bridge(dev, bus) {
1c02ea81006548a Mika Westerberg 2017-10-13 2901 cmax = max;
1c02ea81006548a Mika Westerberg 2017-10-13 2902 max = pci_scan_bridge_extend(bus, dev, max, 0, 0);
3374c545c27c535 Mika Westerberg 2018-05-28 2903
3374c545c27c535 Mika Westerberg 2018-05-28 2904 /*
3374c545c27c535 Mika Westerberg 2018-05-28 2905 * Reserve one bus for each bridge now to avoid extending
3374c545c27c535 Mika Westerberg 2018-05-28 2906 * hotplug bridges too much during the second scan below.
3374c545c27c535 Mika Westerberg 2018-05-28 2907 */
3374c545c27c535 Mika Westerberg 2018-05-28 2908 used_buses++;
3374c545c27c535 Mika Westerberg 2018-05-28 2909 if (cmax - max > 1)
3374c545c27c535 Mika Westerberg 2018-05-28 2910 used_buses += cmax - max - 1;
1c02ea81006548a Mika Westerberg 2017-10-13 2911 }
4147c2fd9b12ae1 Mika Westerberg 2017-10-13 2912
4147c2fd9b12ae1 Mika Westerberg 2017-10-13 2913 /* Scan bridges that need to be reconfigured */
1c02ea81006548a Mika Westerberg 2017-10-13 2914 for_each_pci_bridge(dev, bus) {
1c02ea81006548a Mika Westerberg 2017-10-13 2915 unsigned int buses = 0;
1c02ea81006548a Mika Westerberg 2017-10-13 2916
1c02ea81006548a Mika Westerberg 2017-10-13 2917 if (!hotplug_bridges && normal_bridges == 1) {
3e466e2d3a04c72 Bjorn Helgaas 2017-11-30 2918
1c02ea81006548a Mika Westerberg 2017-10-13 2919 /*
1c02ea81006548a Mika Westerberg 2017-10-13 2920 * There is only one bridge on the bus (upstream
1c02ea81006548a Mika Westerberg 2017-10-13 2921 * port) so it gets all available buses which it
1c02ea81006548a Mika Westerberg 2017-10-13 2922 * can then distribute to the possible hotplug
1c02ea81006548a Mika Westerberg 2017-10-13 2923 * bridges below.
1c02ea81006548a Mika Westerberg 2017-10-13 2924 */
1c02ea81006548a Mika Westerberg 2017-10-13 2925 buses = available_buses;
1c02ea81006548a Mika Westerberg 2017-10-13 2926 } else if (dev->is_hotplug_bridge) {
3e466e2d3a04c72 Bjorn Helgaas 2017-11-30 2927
1c02ea81006548a Mika Westerberg 2017-10-13 2928 /*
1c02ea81006548a Mika Westerberg 2017-10-13 2929 * Distribute the extra buses between hotplug
1c02ea81006548a Mika Westerberg 2017-10-13 2930 * bridges if any.
1c02ea81006548a Mika Westerberg 2017-10-13 2931 */
1c02ea81006548a Mika Westerberg 2017-10-13 2932 buses = available_buses / hotplug_bridges;
3374c545c27c535 Mika Westerberg 2018-05-28 2933 buses = min(buses, available_buses - used_buses + 1);
1c02ea81006548a Mika Westerberg 2017-10-13 2934 }
1c02ea81006548a Mika Westerberg 2017-10-13 2935
1c02ea81006548a Mika Westerberg 2017-10-13 2936 cmax = max;
1c02ea81006548a Mika Westerberg 2017-10-13 2937 max = pci_scan_bridge_extend(bus, dev, cmax, buses, 1);
3374c545c27c535 Mika Westerberg 2018-05-28 2938 /* One bus is already accounted so don't add it again */
3374c545c27c535 Mika Westerberg 2018-05-28 2939 if (max - cmax > 1)
3374c545c27c535 Mika Westerberg 2018-05-28 2940 used_buses += max - cmax - 1;
1c02ea81006548a Mika Westerberg 2017-10-13 2941 }
^1da177e4c3f415 Linus Torvalds 2005-04-16 2942
e16b46605960bd0 Keith Busch 2016-07-21 2943 /*
e16b46605960bd0 Keith Busch 2016-07-21 2944 * Make sure a hotplug bridge has at least the minimum requested
1c02ea81006548a Mika Westerberg 2017-10-13 2945 * number of buses but allow it to grow up to the maximum available
1c02ea81006548a Mika Westerberg 2017-10-13 2946 * bus number of there is room.
e16b46605960bd0 Keith Busch 2016-07-21 2947 */
1c02ea81006548a Mika Westerberg 2017-10-13 2948 if (bus->self && bus->self->is_hotplug_bridge) {
1c02ea81006548a Mika Westerberg 2017-10-13 2949 used_buses = max_t(unsigned int, available_buses,
1c02ea81006548a Mika Westerberg 2017-10-13 2950 pci_hotplug_bus_size - 1);
1c02ea81006548a Mika Westerberg 2017-10-13 2951 if (max - start < used_buses) {
1c02ea81006548a Mika Westerberg 2017-10-13 2952 max = start + used_buses;
a20c7f36bd3d20d Mika Westerberg 2017-10-13 2953
a20c7f36bd3d20d Mika Westerberg 2017-10-13 2954 /* Do not allocate more buses than we have room left */
a20c7f36bd3d20d Mika Westerberg 2017-10-13 2955 if (max > bus->busn_res.end)
a20c7f36bd3d20d Mika Westerberg 2017-10-13 2956 max = bus->busn_res.end;
1c02ea81006548a Mika Westerberg 2017-10-13 2957
1c02ea81006548a Mika Westerberg 2017-10-13 2958 dev_dbg(&bus->dev, "%pR extended by %#02x\n",
1c02ea81006548a Mika Westerberg 2017-10-13 2959 &bus->busn_res, max - start);
1c02ea81006548a Mika Westerberg 2017-10-13 2960 }
e16b46605960bd0 Keith Busch 2016-07-21 2961 }
e16b46605960bd0 Keith Busch 2016-07-21 2962
^1da177e4c3f415 Linus Torvalds 2005-04-16 2963 /*
^1da177e4c3f415 Linus Torvalds 2005-04-16 2964 * We've scanned the bus and so we know all about what's on
^1da177e4c3f415 Linus Torvalds 2005-04-16 2965 * the other side of any bridges that may be on this bus plus
^1da177e4c3f415 Linus Torvalds 2005-04-16 2966 * any devices.
^1da177e4c3f415 Linus Torvalds 2005-04-16 2967 *
^1da177e4c3f415 Linus Torvalds 2005-04-16 2968 * Return how far we've got finding sub-buses.
^1da177e4c3f415 Linus Torvalds 2005-04-16 2969 */
0207c356ef0e2ba Bjorn Helgaas 2009-11-04 2970 dev_dbg(&bus->dev, "bus scan returning with max=%02x\n", max);
^1da177e4c3f415 Linus Torvalds 2005-04-16 2971 return max;
^1da177e4c3f415 Linus Torvalds 2005-04-16 2972 }
1c02ea81006548a Mika Westerberg 2017-10-13 2973
--
0-DAY CI Kernel Test Service
https://01.org/lkp
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v2 2/4] PCI: Move jailhouse's isolated function handling to pci_scan_slot()
2022-04-12 16:28 ` kernel test robot
@ 2022-04-13 7:55 ` Niklas Schnelle
0 siblings, 0 replies; 6+ messages in thread
From: Niklas Schnelle @ 2022-04-13 7:55 UTC (permalink / raw)
To: kernel test robot, Bjorn Helgaas, Jan Kiszka, Matthew Rosato,
Pierre Morel
Cc: kbuild-all, linux-s390, linux-pci
On Wed, 2022-04-13 at 00:28 +0800, kernel test robot wrote:
> Hi Niklas,
>
> I love your patch! Perhaps something to improve:
>
> [auto build test WARNING on helgaas-pci/next]
> [also build test WARNING on s390/features tip/x86/core v5.18-rc2 next-20220412]
> [If your patch is applied to the wrong git tree, kindly drop us a note.
> And when submitting patch, we suggest to use '--base' as documented in
> https://git-scm.com/docs/git-format-patch]
>
> url: https://github.com/intel-lab-lkp/linux/commits/Niklas-Schnelle/PCI-Rework-pci_scan_slot-and-isolated-PCI-functions/20220412-223307
> base: https://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci.git next
> config: alpha-defconfig (https://download.01.org/0day-ci/archive/20220413/202204130045.AeSigvk8-lkp@intel.com/config)
> compiler: alpha-linux-gcc (GCC) 11.2.0
> reproduce (this is a W=1 build):
> wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
> chmod +x ~/bin/make.cross
> # https://github.com/intel-lab-lkp/linux/commit/5cac6729750b7434ff5d6ae99469e9e54bc9fb6e
> git remote add linux-review https://github.com/intel-lab-lkp/linux
> git fetch --no-tags linux-review Niklas-Schnelle/PCI-Rework-pci_scan_slot-and-isolated-PCI-functions/20220412-223307
> git checkout 5cac6729750b7434ff5d6ae99469e9e54bc9fb6e
> # save the config file to linux build tree
> mkdir build_dir
> COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross O=build_dir ARCH=alpha SHELL=/bin/bash drivers/pci/
>
> If you fix the issue, kindly add following tag as appropriate
> Reported-by: kernel test robot <lkp@intel.com>
>
> All warnings (new ones prefixed by >>):
>
> drivers/pci/probe.c: In function 'pci_scan_child_bus_extend':
> > > drivers/pci/probe.c:2861:13: warning: variable 'nr_devs' set but not used [-Wunused-but-set-variable]
> 2861 | int nr_devs;
> | ^~~~~~~
>
>
> vim +/nr_devs +2861 drivers/pci/probe.c
>
> bccf90d6e063d2 Palmer Dabbelt 2017-06-23 2841
> 1c02ea81006548 Mika Westerberg 2017-10-13 2842 /**
> 1c02ea81006548 Mika Westerberg 2017-10-13 2843 * pci_scan_child_bus_extend() - Scan devices below a bus
> 1c02ea81006548 Mika Westerberg 2017-10-13 2844 * @bus: Bus to scan for devices
> 1c02ea81006548 Mika Westerberg 2017-10-13 2845 * @available_buses: Total number of buses available (%0 does not try to
> 1c02ea81006548 Mika Westerberg 2017-10-13 2846 * extend beyond the minimal)
> 1c02ea81006548 Mika Westerberg 2017-10-13 2847 *
> 1c02ea81006548 Mika Westerberg 2017-10-13 2848 * Scans devices below @bus including subordinate buses. Returns new
> 1c02ea81006548 Mika Westerberg 2017-10-13 2849 * subordinate number including all the found devices. Passing
> 1c02ea81006548 Mika Westerberg 2017-10-13 2850 * @available_buses causes the remaining bus space to be distributed
> 1c02ea81006548 Mika Westerberg 2017-10-13 2851 * equally between hotplug-capable bridges to allow future extension of the
> 1c02ea81006548 Mika Westerberg 2017-10-13 2852 * hierarchy.
> 1c02ea81006548 Mika Westerberg 2017-10-13 2853 */
> 1c02ea81006548 Mika Westerberg 2017-10-13 2854 static unsigned int pci_scan_child_bus_extend(struct pci_bus *bus,
> 1c02ea81006548 Mika Westerberg 2017-10-13 2855 unsigned int available_buses)
> 1c02ea81006548 Mika Westerberg 2017-10-13 2856 {
> 1c02ea81006548 Mika Westerberg 2017-10-13 2857 unsigned int used_buses, normal_bridges = 0, hotplug_bridges = 0;
> 1c02ea81006548 Mika Westerberg 2017-10-13 2858 unsigned int start = bus->busn_res.start;
> 5cac6729750b74 Niklas Schnelle 2022-04-12 2859 unsigned int devfn, cmax, max = start;
> ^1da177e4c3f41 Linus Torvalds 2005-04-16 2860 struct pci_dev *dev;
> 690f4304104f37 Jan Kiszka 2018-03-07 @2861 int nr_devs;
> ^1da177e4c3f41 Linus Torvalds 2005-04-16 2862
> 0207c356ef0e2b Bjorn Helgaas 2009-11-04 2863 dev_dbg(&bus->dev, "scanning bus\n");
> ^1da177e4c3f41 Linus Torvalds 2005-04-16 2864
> ^1da177e4c3f41 Linus Torvalds 2005-04-16 2865 /* Go find them, Rover! */
> 5cac6729750b74 Niklas Schnelle 2022-04-12 2866 for (devfn = 0; devfn < 256; devfn += 8)
> 690f4304104f37 Jan Kiszka 2018-03-07 2867 nr_devs = pci_scan_slot(bus, devfn);
The bot is right, the nr_devs can be removed as the patch removed the
only read access did so locally already.
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v2 2/4] PCI: Move jailhouse's isolated function handling to pci_scan_slot()
@ 2022-04-13 7:55 ` Niklas Schnelle
0 siblings, 0 replies; 6+ messages in thread
From: Niklas Schnelle @ 2022-04-13 7:55 UTC (permalink / raw)
To: kbuild-all
[-- Attachment #1: Type: text/plain, Size: 4553 bytes --]
On Wed, 2022-04-13 at 00:28 +0800, kernel test robot wrote:
> Hi Niklas,
>
> I love your patch! Perhaps something to improve:
>
> [auto build test WARNING on helgaas-pci/next]
> [also build test WARNING on s390/features tip/x86/core v5.18-rc2 next-20220412]
> [If your patch is applied to the wrong git tree, kindly drop us a note.
> And when submitting patch, we suggest to use '--base' as documented in
> https://git-scm.com/docs/git-format-patch]
>
> url: https://github.com/intel-lab-lkp/linux/commits/Niklas-Schnelle/PCI-Rework-pci_scan_slot-and-isolated-PCI-functions/20220412-223307
> base: https://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci.git next
> config: alpha-defconfig (https://download.01.org/0day-ci/archive/20220413/202204130045.AeSigvk8-lkp(a)intel.com/config)
> compiler: alpha-linux-gcc (GCC) 11.2.0
> reproduce (this is a W=1 build):
> wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
> chmod +x ~/bin/make.cross
> # https://github.com/intel-lab-lkp/linux/commit/5cac6729750b7434ff5d6ae99469e9e54bc9fb6e
> git remote add linux-review https://github.com/intel-lab-lkp/linux
> git fetch --no-tags linux-review Niklas-Schnelle/PCI-Rework-pci_scan_slot-and-isolated-PCI-functions/20220412-223307
> git checkout 5cac6729750b7434ff5d6ae99469e9e54bc9fb6e
> # save the config file to linux build tree
> mkdir build_dir
> COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross O=build_dir ARCH=alpha SHELL=/bin/bash drivers/pci/
>
> If you fix the issue, kindly add following tag as appropriate
> Reported-by: kernel test robot <lkp@intel.com>
>
> All warnings (new ones prefixed by >>):
>
> drivers/pci/probe.c: In function 'pci_scan_child_bus_extend':
> > > drivers/pci/probe.c:2861:13: warning: variable 'nr_devs' set but not used [-Wunused-but-set-variable]
> 2861 | int nr_devs;
> | ^~~~~~~
>
>
> vim +/nr_devs +2861 drivers/pci/probe.c
>
> bccf90d6e063d2 Palmer Dabbelt 2017-06-23 2841
> 1c02ea81006548 Mika Westerberg 2017-10-13 2842 /**
> 1c02ea81006548 Mika Westerberg 2017-10-13 2843 * pci_scan_child_bus_extend() - Scan devices below a bus
> 1c02ea81006548 Mika Westerberg 2017-10-13 2844 * @bus: Bus to scan for devices
> 1c02ea81006548 Mika Westerberg 2017-10-13 2845 * @available_buses: Total number of buses available (%0 does not try to
> 1c02ea81006548 Mika Westerberg 2017-10-13 2846 * extend beyond the minimal)
> 1c02ea81006548 Mika Westerberg 2017-10-13 2847 *
> 1c02ea81006548 Mika Westerberg 2017-10-13 2848 * Scans devices below @bus including subordinate buses. Returns new
> 1c02ea81006548 Mika Westerberg 2017-10-13 2849 * subordinate number including all the found devices. Passing
> 1c02ea81006548 Mika Westerberg 2017-10-13 2850 * @available_buses causes the remaining bus space to be distributed
> 1c02ea81006548 Mika Westerberg 2017-10-13 2851 * equally between hotplug-capable bridges to allow future extension of the
> 1c02ea81006548 Mika Westerberg 2017-10-13 2852 * hierarchy.
> 1c02ea81006548 Mika Westerberg 2017-10-13 2853 */
> 1c02ea81006548 Mika Westerberg 2017-10-13 2854 static unsigned int pci_scan_child_bus_extend(struct pci_bus *bus,
> 1c02ea81006548 Mika Westerberg 2017-10-13 2855 unsigned int available_buses)
> 1c02ea81006548 Mika Westerberg 2017-10-13 2856 {
> 1c02ea81006548 Mika Westerberg 2017-10-13 2857 unsigned int used_buses, normal_bridges = 0, hotplug_bridges = 0;
> 1c02ea81006548 Mika Westerberg 2017-10-13 2858 unsigned int start = bus->busn_res.start;
> 5cac6729750b74 Niklas Schnelle 2022-04-12 2859 unsigned int devfn, cmax, max = start;
> ^1da177e4c3f41 Linus Torvalds 2005-04-16 2860 struct pci_dev *dev;
> 690f4304104f37 Jan Kiszka 2018-03-07 @2861 int nr_devs;
> ^1da177e4c3f41 Linus Torvalds 2005-04-16 2862
> 0207c356ef0e2b Bjorn Helgaas 2009-11-04 2863 dev_dbg(&bus->dev, "scanning bus\n");
> ^1da177e4c3f41 Linus Torvalds 2005-04-16 2864
> ^1da177e4c3f41 Linus Torvalds 2005-04-16 2865 /* Go find them, Rover! */
> 5cac6729750b74 Niklas Schnelle 2022-04-12 2866 for (devfn = 0; devfn < 256; devfn += 8)
> 690f4304104f37 Jan Kiszka 2018-03-07 2867 nr_devs = pci_scan_slot(bus, devfn);
The bot is right, the nr_devs can be removed as the patch removed the
only read access did so locally already.
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v2 2/4] PCI: Move jailhouse's isolated function handling to pci_scan_slot()
2022-04-12 14:30 ` [PATCH v2 2/4] PCI: Move jailhouse's isolated function handling to pci_scan_slot() Niklas Schnelle
2022-04-12 16:28 ` kernel test robot
@ 2022-04-12 19:43 ` kernel test robot
1 sibling, 0 replies; 6+ messages in thread
From: kernel test robot @ 2022-04-12 19:43 UTC (permalink / raw)
To: Niklas Schnelle, Bjorn Helgaas, Jan Kiszka, Matthew Rosato, Pierre Morel
Cc: llvm, kbuild-all, linux-s390, linux-pci
Hi Niklas,
I love your patch! Perhaps something to improve:
[auto build test WARNING on helgaas-pci/next]
[also build test WARNING on s390/features tip/x86/core v5.18-rc2 next-20220412]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/intel-lab-lkp/linux/commits/Niklas-Schnelle/PCI-Rework-pci_scan_slot-and-isolated-PCI-functions/20220412-223307
base: https://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci.git next
config: i386-randconfig-a003-20220411 (https://download.01.org/0day-ci/archive/20220413/202204130326.eQ0YpxtC-lkp@intel.com/config)
compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project fe2478d44e4f7f191c43fef629ac7a23d0251e72)
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/intel-lab-lkp/linux/commit/5cac6729750b7434ff5d6ae99469e9e54bc9fb6e
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review Niklas-Schnelle/PCI-Rework-pci_scan_slot-and-isolated-PCI-functions/20220412-223307
git checkout 5cac6729750b7434ff5d6ae99469e9e54bc9fb6e
# save the config file to linux build tree
mkdir build_dir
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=i386 SHELL=/bin/bash drivers/pci/
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
All warnings (new ones prefixed by >>):
>> drivers/pci/probe.c:2861:6: warning: variable 'nr_devs' set but not used [-Wunused-but-set-variable]
int nr_devs;
^
1 warning generated.
vim +/nr_devs +2861 drivers/pci/probe.c
bccf90d6e063d27 Palmer Dabbelt 2017-06-23 2841
1c02ea81006548a Mika Westerberg 2017-10-13 2842 /**
1c02ea81006548a Mika Westerberg 2017-10-13 2843 * pci_scan_child_bus_extend() - Scan devices below a bus
1c02ea81006548a Mika Westerberg 2017-10-13 2844 * @bus: Bus to scan for devices
1c02ea81006548a Mika Westerberg 2017-10-13 2845 * @available_buses: Total number of buses available (%0 does not try to
1c02ea81006548a Mika Westerberg 2017-10-13 2846 * extend beyond the minimal)
1c02ea81006548a Mika Westerberg 2017-10-13 2847 *
1c02ea81006548a Mika Westerberg 2017-10-13 2848 * Scans devices below @bus including subordinate buses. Returns new
1c02ea81006548a Mika Westerberg 2017-10-13 2849 * subordinate number including all the found devices. Passing
1c02ea81006548a Mika Westerberg 2017-10-13 2850 * @available_buses causes the remaining bus space to be distributed
1c02ea81006548a Mika Westerberg 2017-10-13 2851 * equally between hotplug-capable bridges to allow future extension of the
1c02ea81006548a Mika Westerberg 2017-10-13 2852 * hierarchy.
1c02ea81006548a Mika Westerberg 2017-10-13 2853 */
1c02ea81006548a Mika Westerberg 2017-10-13 2854 static unsigned int pci_scan_child_bus_extend(struct pci_bus *bus,
1c02ea81006548a Mika Westerberg 2017-10-13 2855 unsigned int available_buses)
1c02ea81006548a Mika Westerberg 2017-10-13 2856 {
1c02ea81006548a Mika Westerberg 2017-10-13 2857 unsigned int used_buses, normal_bridges = 0, hotplug_bridges = 0;
1c02ea81006548a Mika Westerberg 2017-10-13 2858 unsigned int start = bus->busn_res.start;
5cac6729750b743 Niklas Schnelle 2022-04-12 2859 unsigned int devfn, cmax, max = start;
^1da177e4c3f415 Linus Torvalds 2005-04-16 2860 struct pci_dev *dev;
690f4304104f37e Jan Kiszka 2018-03-07 @2861 int nr_devs;
^1da177e4c3f415 Linus Torvalds 2005-04-16 2862
0207c356ef0e2ba Bjorn Helgaas 2009-11-04 2863 dev_dbg(&bus->dev, "scanning bus\n");
^1da177e4c3f415 Linus Torvalds 2005-04-16 2864
^1da177e4c3f415 Linus Torvalds 2005-04-16 2865 /* Go find them, Rover! */
5cac6729750b743 Niklas Schnelle 2022-04-12 2866 for (devfn = 0; devfn < 256; devfn += 8)
690f4304104f37e Jan Kiszka 2018-03-07 2867 nr_devs = pci_scan_slot(bus, devfn);
690f4304104f37e Jan Kiszka 2018-03-07 2868
3e466e2d3a04c72 Bjorn Helgaas 2017-11-30 2869 /* Reserve buses for SR-IOV capability */
1c02ea81006548a Mika Westerberg 2017-10-13 2870 used_buses = pci_iov_bus_range(bus);
1c02ea81006548a Mika Westerberg 2017-10-13 2871 max += used_buses;
a28724b0fb909d2 Yu Zhao 2009-03-20 2872
^1da177e4c3f415 Linus Torvalds 2005-04-16 2873 /*
^1da177e4c3f415 Linus Torvalds 2005-04-16 2874 * After performing arch-dependent fixup of the bus, look behind
^1da177e4c3f415 Linus Torvalds 2005-04-16 2875 * all PCI-to-PCI bridges on this bus.
^1da177e4c3f415 Linus Torvalds 2005-04-16 2876 */
74710ded8e16fc8 Alex Chiang 2009-03-20 2877 if (!bus->is_added) {
0207c356ef0e2ba Bjorn Helgaas 2009-11-04 2878 dev_dbg(&bus->dev, "fixups for bus\n");
^1da177e4c3f415 Linus Torvalds 2005-04-16 2879 pcibios_fixup_bus(bus);
74710ded8e16fc8 Alex Chiang 2009-03-20 2880 bus->is_added = 1;
74710ded8e16fc8 Alex Chiang 2009-03-20 2881 }
74710ded8e16fc8 Alex Chiang 2009-03-20 2882
1c02ea81006548a Mika Westerberg 2017-10-13 2883 /*
1c02ea81006548a Mika Westerberg 2017-10-13 2884 * Calculate how many hotplug bridges and normal bridges there
1c02ea81006548a Mika Westerberg 2017-10-13 2885 * are on this bus. We will distribute the additional available
1c02ea81006548a Mika Westerberg 2017-10-13 2886 * buses between hotplug bridges.
1c02ea81006548a Mika Westerberg 2017-10-13 2887 */
1c02ea81006548a Mika Westerberg 2017-10-13 2888 for_each_pci_bridge(dev, bus) {
1c02ea81006548a Mika Westerberg 2017-10-13 2889 if (dev->is_hotplug_bridge)
1c02ea81006548a Mika Westerberg 2017-10-13 2890 hotplug_bridges++;
1c02ea81006548a Mika Westerberg 2017-10-13 2891 else
1c02ea81006548a Mika Westerberg 2017-10-13 2892 normal_bridges++;
1c02ea81006548a Mika Westerberg 2017-10-13 2893 }
1c02ea81006548a Mika Westerberg 2017-10-13 2894
4147c2fd9b12ae1 Mika Westerberg 2017-10-13 2895 /*
4147c2fd9b12ae1 Mika Westerberg 2017-10-13 2896 * Scan bridges that are already configured. We don't touch them
4147c2fd9b12ae1 Mika Westerberg 2017-10-13 2897 * unless they are misconfigured (which will be done in the second
4147c2fd9b12ae1 Mika Westerberg 2017-10-13 2898 * scan below).
4147c2fd9b12ae1 Mika Westerberg 2017-10-13 2899 */
1c02ea81006548a Mika Westerberg 2017-10-13 2900 for_each_pci_bridge(dev, bus) {
1c02ea81006548a Mika Westerberg 2017-10-13 2901 cmax = max;
1c02ea81006548a Mika Westerberg 2017-10-13 2902 max = pci_scan_bridge_extend(bus, dev, max, 0, 0);
3374c545c27c535 Mika Westerberg 2018-05-28 2903
3374c545c27c535 Mika Westerberg 2018-05-28 2904 /*
3374c545c27c535 Mika Westerberg 2018-05-28 2905 * Reserve one bus for each bridge now to avoid extending
3374c545c27c535 Mika Westerberg 2018-05-28 2906 * hotplug bridges too much during the second scan below.
3374c545c27c535 Mika Westerberg 2018-05-28 2907 */
3374c545c27c535 Mika Westerberg 2018-05-28 2908 used_buses++;
3374c545c27c535 Mika Westerberg 2018-05-28 2909 if (cmax - max > 1)
3374c545c27c535 Mika Westerberg 2018-05-28 2910 used_buses += cmax - max - 1;
1c02ea81006548a Mika Westerberg 2017-10-13 2911 }
4147c2fd9b12ae1 Mika Westerberg 2017-10-13 2912
4147c2fd9b12ae1 Mika Westerberg 2017-10-13 2913 /* Scan bridges that need to be reconfigured */
1c02ea81006548a Mika Westerberg 2017-10-13 2914 for_each_pci_bridge(dev, bus) {
1c02ea81006548a Mika Westerberg 2017-10-13 2915 unsigned int buses = 0;
1c02ea81006548a Mika Westerberg 2017-10-13 2916
1c02ea81006548a Mika Westerberg 2017-10-13 2917 if (!hotplug_bridges && normal_bridges == 1) {
3e466e2d3a04c72 Bjorn Helgaas 2017-11-30 2918
1c02ea81006548a Mika Westerberg 2017-10-13 2919 /*
1c02ea81006548a Mika Westerberg 2017-10-13 2920 * There is only one bridge on the bus (upstream
1c02ea81006548a Mika Westerberg 2017-10-13 2921 * port) so it gets all available buses which it
1c02ea81006548a Mika Westerberg 2017-10-13 2922 * can then distribute to the possible hotplug
1c02ea81006548a Mika Westerberg 2017-10-13 2923 * bridges below.
1c02ea81006548a Mika Westerberg 2017-10-13 2924 */
1c02ea81006548a Mika Westerberg 2017-10-13 2925 buses = available_buses;
1c02ea81006548a Mika Westerberg 2017-10-13 2926 } else if (dev->is_hotplug_bridge) {
3e466e2d3a04c72 Bjorn Helgaas 2017-11-30 2927
1c02ea81006548a Mika Westerberg 2017-10-13 2928 /*
1c02ea81006548a Mika Westerberg 2017-10-13 2929 * Distribute the extra buses between hotplug
1c02ea81006548a Mika Westerberg 2017-10-13 2930 * bridges if any.
1c02ea81006548a Mika Westerberg 2017-10-13 2931 */
1c02ea81006548a Mika Westerberg 2017-10-13 2932 buses = available_buses / hotplug_bridges;
3374c545c27c535 Mika Westerberg 2018-05-28 2933 buses = min(buses, available_buses - used_buses + 1);
1c02ea81006548a Mika Westerberg 2017-10-13 2934 }
1c02ea81006548a Mika Westerberg 2017-10-13 2935
1c02ea81006548a Mika Westerberg 2017-10-13 2936 cmax = max;
1c02ea81006548a Mika Westerberg 2017-10-13 2937 max = pci_scan_bridge_extend(bus, dev, cmax, buses, 1);
3374c545c27c535 Mika Westerberg 2018-05-28 2938 /* One bus is already accounted so don't add it again */
3374c545c27c535 Mika Westerberg 2018-05-28 2939 if (max - cmax > 1)
3374c545c27c535 Mika Westerberg 2018-05-28 2940 used_buses += max - cmax - 1;
1c02ea81006548a Mika Westerberg 2017-10-13 2941 }
^1da177e4c3f415 Linus Torvalds 2005-04-16 2942
e16b46605960bd0 Keith Busch 2016-07-21 2943 /*
e16b46605960bd0 Keith Busch 2016-07-21 2944 * Make sure a hotplug bridge has at least the minimum requested
1c02ea81006548a Mika Westerberg 2017-10-13 2945 * number of buses but allow it to grow up to the maximum available
1c02ea81006548a Mika Westerberg 2017-10-13 2946 * bus number of there is room.
e16b46605960bd0 Keith Busch 2016-07-21 2947 */
1c02ea81006548a Mika Westerberg 2017-10-13 2948 if (bus->self && bus->self->is_hotplug_bridge) {
1c02ea81006548a Mika Westerberg 2017-10-13 2949 used_buses = max_t(unsigned int, available_buses,
1c02ea81006548a Mika Westerberg 2017-10-13 2950 pci_hotplug_bus_size - 1);
1c02ea81006548a Mika Westerberg 2017-10-13 2951 if (max - start < used_buses) {
1c02ea81006548a Mika Westerberg 2017-10-13 2952 max = start + used_buses;
a20c7f36bd3d20d Mika Westerberg 2017-10-13 2953
a20c7f36bd3d20d Mika Westerberg 2017-10-13 2954 /* Do not allocate more buses than we have room left */
a20c7f36bd3d20d Mika Westerberg 2017-10-13 2955 if (max > bus->busn_res.end)
a20c7f36bd3d20d Mika Westerberg 2017-10-13 2956 max = bus->busn_res.end;
1c02ea81006548a Mika Westerberg 2017-10-13 2957
1c02ea81006548a Mika Westerberg 2017-10-13 2958 dev_dbg(&bus->dev, "%pR extended by %#02x\n",
1c02ea81006548a Mika Westerberg 2017-10-13 2959 &bus->busn_res, max - start);
1c02ea81006548a Mika Westerberg 2017-10-13 2960 }
e16b46605960bd0 Keith Busch 2016-07-21 2961 }
e16b46605960bd0 Keith Busch 2016-07-21 2962
^1da177e4c3f415 Linus Torvalds 2005-04-16 2963 /*
^1da177e4c3f415 Linus Torvalds 2005-04-16 2964 * We've scanned the bus and so we know all about what's on
^1da177e4c3f415 Linus Torvalds 2005-04-16 2965 * the other side of any bridges that may be on this bus plus
^1da177e4c3f415 Linus Torvalds 2005-04-16 2966 * any devices.
^1da177e4c3f415 Linus Torvalds 2005-04-16 2967 *
^1da177e4c3f415 Linus Torvalds 2005-04-16 2968 * Return how far we've got finding sub-buses.
^1da177e4c3f415 Linus Torvalds 2005-04-16 2969 */
0207c356ef0e2ba Bjorn Helgaas 2009-11-04 2970 dev_dbg(&bus->dev, "bus scan returning with max=%02x\n", max);
^1da177e4c3f415 Linus Torvalds 2005-04-16 2971 return max;
^1da177e4c3f415 Linus Torvalds 2005-04-16 2972 }
1c02ea81006548a Mika Westerberg 2017-10-13 2973
--
0-DAY CI Kernel Test Service
https://01.org/lkp
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v2 2/4] PCI: Move jailhouse's isolated function handling to pci_scan_slot()
2022-04-12 14:30 ` [PATCH v2 2/4] PCI: Move jailhouse's isolated function handling to pci_scan_slot() Niklas Schnelle
@ 2022-04-12 16:28 ` kernel test robot
2022-04-13 7:55 ` Niklas Schnelle
2022-04-12 19:43 ` kernel test robot
1 sibling, 1 reply; 6+ messages in thread
From: kernel test robot @ 2022-04-12 16:28 UTC (permalink / raw)
To: Niklas Schnelle, Bjorn Helgaas, Jan Kiszka, Matthew Rosato, Pierre Morel
Cc: kbuild-all, linux-s390, linux-pci
Hi Niklas,
I love your patch! Perhaps something to improve:
[auto build test WARNING on helgaas-pci/next]
[also build test WARNING on s390/features tip/x86/core v5.18-rc2 next-20220412]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/intel-lab-lkp/linux/commits/Niklas-Schnelle/PCI-Rework-pci_scan_slot-and-isolated-PCI-functions/20220412-223307
base: https://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci.git next
config: alpha-defconfig (https://download.01.org/0day-ci/archive/20220413/202204130045.AeSigvk8-lkp@intel.com/config)
compiler: alpha-linux-gcc (GCC) 11.2.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/intel-lab-lkp/linux/commit/5cac6729750b7434ff5d6ae99469e9e54bc9fb6e
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review Niklas-Schnelle/PCI-Rework-pci_scan_slot-and-isolated-PCI-functions/20220412-223307
git checkout 5cac6729750b7434ff5d6ae99469e9e54bc9fb6e
# save the config file to linux build tree
mkdir build_dir
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross O=build_dir ARCH=alpha SHELL=/bin/bash drivers/pci/
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
All warnings (new ones prefixed by >>):
drivers/pci/probe.c: In function 'pci_scan_child_bus_extend':
>> drivers/pci/probe.c:2861:13: warning: variable 'nr_devs' set but not used [-Wunused-but-set-variable]
2861 | int nr_devs;
| ^~~~~~~
vim +/nr_devs +2861 drivers/pci/probe.c
bccf90d6e063d2 Palmer Dabbelt 2017-06-23 2841
1c02ea81006548 Mika Westerberg 2017-10-13 2842 /**
1c02ea81006548 Mika Westerberg 2017-10-13 2843 * pci_scan_child_bus_extend() - Scan devices below a bus
1c02ea81006548 Mika Westerberg 2017-10-13 2844 * @bus: Bus to scan for devices
1c02ea81006548 Mika Westerberg 2017-10-13 2845 * @available_buses: Total number of buses available (%0 does not try to
1c02ea81006548 Mika Westerberg 2017-10-13 2846 * extend beyond the minimal)
1c02ea81006548 Mika Westerberg 2017-10-13 2847 *
1c02ea81006548 Mika Westerberg 2017-10-13 2848 * Scans devices below @bus including subordinate buses. Returns new
1c02ea81006548 Mika Westerberg 2017-10-13 2849 * subordinate number including all the found devices. Passing
1c02ea81006548 Mika Westerberg 2017-10-13 2850 * @available_buses causes the remaining bus space to be distributed
1c02ea81006548 Mika Westerberg 2017-10-13 2851 * equally between hotplug-capable bridges to allow future extension of the
1c02ea81006548 Mika Westerberg 2017-10-13 2852 * hierarchy.
1c02ea81006548 Mika Westerberg 2017-10-13 2853 */
1c02ea81006548 Mika Westerberg 2017-10-13 2854 static unsigned int pci_scan_child_bus_extend(struct pci_bus *bus,
1c02ea81006548 Mika Westerberg 2017-10-13 2855 unsigned int available_buses)
1c02ea81006548 Mika Westerberg 2017-10-13 2856 {
1c02ea81006548 Mika Westerberg 2017-10-13 2857 unsigned int used_buses, normal_bridges = 0, hotplug_bridges = 0;
1c02ea81006548 Mika Westerberg 2017-10-13 2858 unsigned int start = bus->busn_res.start;
5cac6729750b74 Niklas Schnelle 2022-04-12 2859 unsigned int devfn, cmax, max = start;
^1da177e4c3f41 Linus Torvalds 2005-04-16 2860 struct pci_dev *dev;
690f4304104f37 Jan Kiszka 2018-03-07 @2861 int nr_devs;
^1da177e4c3f41 Linus Torvalds 2005-04-16 2862
0207c356ef0e2b Bjorn Helgaas 2009-11-04 2863 dev_dbg(&bus->dev, "scanning bus\n");
^1da177e4c3f41 Linus Torvalds 2005-04-16 2864
^1da177e4c3f41 Linus Torvalds 2005-04-16 2865 /* Go find them, Rover! */
5cac6729750b74 Niklas Schnelle 2022-04-12 2866 for (devfn = 0; devfn < 256; devfn += 8)
690f4304104f37 Jan Kiszka 2018-03-07 2867 nr_devs = pci_scan_slot(bus, devfn);
690f4304104f37 Jan Kiszka 2018-03-07 2868
3e466e2d3a04c7 Bjorn Helgaas 2017-11-30 2869 /* Reserve buses for SR-IOV capability */
1c02ea81006548 Mika Westerberg 2017-10-13 2870 used_buses = pci_iov_bus_range(bus);
1c02ea81006548 Mika Westerberg 2017-10-13 2871 max += used_buses;
a28724b0fb909d Yu Zhao 2009-03-20 2872
^1da177e4c3f41 Linus Torvalds 2005-04-16 2873 /*
^1da177e4c3f41 Linus Torvalds 2005-04-16 2874 * After performing arch-dependent fixup of the bus, look behind
^1da177e4c3f41 Linus Torvalds 2005-04-16 2875 * all PCI-to-PCI bridges on this bus.
^1da177e4c3f41 Linus Torvalds 2005-04-16 2876 */
74710ded8e16fc Alex Chiang 2009-03-20 2877 if (!bus->is_added) {
0207c356ef0e2b Bjorn Helgaas 2009-11-04 2878 dev_dbg(&bus->dev, "fixups for bus\n");
^1da177e4c3f41 Linus Torvalds 2005-04-16 2879 pcibios_fixup_bus(bus);
74710ded8e16fc Alex Chiang 2009-03-20 2880 bus->is_added = 1;
74710ded8e16fc Alex Chiang 2009-03-20 2881 }
74710ded8e16fc Alex Chiang 2009-03-20 2882
1c02ea81006548 Mika Westerberg 2017-10-13 2883 /*
1c02ea81006548 Mika Westerberg 2017-10-13 2884 * Calculate how many hotplug bridges and normal bridges there
1c02ea81006548 Mika Westerberg 2017-10-13 2885 * are on this bus. We will distribute the additional available
1c02ea81006548 Mika Westerberg 2017-10-13 2886 * buses between hotplug bridges.
1c02ea81006548 Mika Westerberg 2017-10-13 2887 */
1c02ea81006548 Mika Westerberg 2017-10-13 2888 for_each_pci_bridge(dev, bus) {
1c02ea81006548 Mika Westerberg 2017-10-13 2889 if (dev->is_hotplug_bridge)
1c02ea81006548 Mika Westerberg 2017-10-13 2890 hotplug_bridges++;
1c02ea81006548 Mika Westerberg 2017-10-13 2891 else
1c02ea81006548 Mika Westerberg 2017-10-13 2892 normal_bridges++;
1c02ea81006548 Mika Westerberg 2017-10-13 2893 }
1c02ea81006548 Mika Westerberg 2017-10-13 2894
4147c2fd9b12ae Mika Westerberg 2017-10-13 2895 /*
4147c2fd9b12ae Mika Westerberg 2017-10-13 2896 * Scan bridges that are already configured. We don't touch them
4147c2fd9b12ae Mika Westerberg 2017-10-13 2897 * unless they are misconfigured (which will be done in the second
4147c2fd9b12ae Mika Westerberg 2017-10-13 2898 * scan below).
4147c2fd9b12ae Mika Westerberg 2017-10-13 2899 */
1c02ea81006548 Mika Westerberg 2017-10-13 2900 for_each_pci_bridge(dev, bus) {
1c02ea81006548 Mika Westerberg 2017-10-13 2901 cmax = max;
1c02ea81006548 Mika Westerberg 2017-10-13 2902 max = pci_scan_bridge_extend(bus, dev, max, 0, 0);
3374c545c27c53 Mika Westerberg 2018-05-28 2903
3374c545c27c53 Mika Westerberg 2018-05-28 2904 /*
3374c545c27c53 Mika Westerberg 2018-05-28 2905 * Reserve one bus for each bridge now to avoid extending
3374c545c27c53 Mika Westerberg 2018-05-28 2906 * hotplug bridges too much during the second scan below.
3374c545c27c53 Mika Westerberg 2018-05-28 2907 */
3374c545c27c53 Mika Westerberg 2018-05-28 2908 used_buses++;
3374c545c27c53 Mika Westerberg 2018-05-28 2909 if (cmax - max > 1)
3374c545c27c53 Mika Westerberg 2018-05-28 2910 used_buses += cmax - max - 1;
1c02ea81006548 Mika Westerberg 2017-10-13 2911 }
4147c2fd9b12ae Mika Westerberg 2017-10-13 2912
4147c2fd9b12ae Mika Westerberg 2017-10-13 2913 /* Scan bridges that need to be reconfigured */
1c02ea81006548 Mika Westerberg 2017-10-13 2914 for_each_pci_bridge(dev, bus) {
1c02ea81006548 Mika Westerberg 2017-10-13 2915 unsigned int buses = 0;
1c02ea81006548 Mika Westerberg 2017-10-13 2916
1c02ea81006548 Mika Westerberg 2017-10-13 2917 if (!hotplug_bridges && normal_bridges == 1) {
3e466e2d3a04c7 Bjorn Helgaas 2017-11-30 2918
1c02ea81006548 Mika Westerberg 2017-10-13 2919 /*
1c02ea81006548 Mika Westerberg 2017-10-13 2920 * There is only one bridge on the bus (upstream
1c02ea81006548 Mika Westerberg 2017-10-13 2921 * port) so it gets all available buses which it
1c02ea81006548 Mika Westerberg 2017-10-13 2922 * can then distribute to the possible hotplug
1c02ea81006548 Mika Westerberg 2017-10-13 2923 * bridges below.
1c02ea81006548 Mika Westerberg 2017-10-13 2924 */
1c02ea81006548 Mika Westerberg 2017-10-13 2925 buses = available_buses;
1c02ea81006548 Mika Westerberg 2017-10-13 2926 } else if (dev->is_hotplug_bridge) {
3e466e2d3a04c7 Bjorn Helgaas 2017-11-30 2927
1c02ea81006548 Mika Westerberg 2017-10-13 2928 /*
1c02ea81006548 Mika Westerberg 2017-10-13 2929 * Distribute the extra buses between hotplug
1c02ea81006548 Mika Westerberg 2017-10-13 2930 * bridges if any.
1c02ea81006548 Mika Westerberg 2017-10-13 2931 */
1c02ea81006548 Mika Westerberg 2017-10-13 2932 buses = available_buses / hotplug_bridges;
3374c545c27c53 Mika Westerberg 2018-05-28 2933 buses = min(buses, available_buses - used_buses + 1);
1c02ea81006548 Mika Westerberg 2017-10-13 2934 }
1c02ea81006548 Mika Westerberg 2017-10-13 2935
1c02ea81006548 Mika Westerberg 2017-10-13 2936 cmax = max;
1c02ea81006548 Mika Westerberg 2017-10-13 2937 max = pci_scan_bridge_extend(bus, dev, cmax, buses, 1);
3374c545c27c53 Mika Westerberg 2018-05-28 2938 /* One bus is already accounted so don't add it again */
3374c545c27c53 Mika Westerberg 2018-05-28 2939 if (max - cmax > 1)
3374c545c27c53 Mika Westerberg 2018-05-28 2940 used_buses += max - cmax - 1;
1c02ea81006548 Mika Westerberg 2017-10-13 2941 }
^1da177e4c3f41 Linus Torvalds 2005-04-16 2942
e16b46605960bd Keith Busch 2016-07-21 2943 /*
e16b46605960bd Keith Busch 2016-07-21 2944 * Make sure a hotplug bridge has at least the minimum requested
1c02ea81006548 Mika Westerberg 2017-10-13 2945 * number of buses but allow it to grow up to the maximum available
1c02ea81006548 Mika Westerberg 2017-10-13 2946 * bus number of there is room.
e16b46605960bd Keith Busch 2016-07-21 2947 */
1c02ea81006548 Mika Westerberg 2017-10-13 2948 if (bus->self && bus->self->is_hotplug_bridge) {
1c02ea81006548 Mika Westerberg 2017-10-13 2949 used_buses = max_t(unsigned int, available_buses,
1c02ea81006548 Mika Westerberg 2017-10-13 2950 pci_hotplug_bus_size - 1);
1c02ea81006548 Mika Westerberg 2017-10-13 2951 if (max - start < used_buses) {
1c02ea81006548 Mika Westerberg 2017-10-13 2952 max = start + used_buses;
a20c7f36bd3d20 Mika Westerberg 2017-10-13 2953
a20c7f36bd3d20 Mika Westerberg 2017-10-13 2954 /* Do not allocate more buses than we have room left */
a20c7f36bd3d20 Mika Westerberg 2017-10-13 2955 if (max > bus->busn_res.end)
a20c7f36bd3d20 Mika Westerberg 2017-10-13 2956 max = bus->busn_res.end;
1c02ea81006548 Mika Westerberg 2017-10-13 2957
1c02ea81006548 Mika Westerberg 2017-10-13 2958 dev_dbg(&bus->dev, "%pR extended by %#02x\n",
1c02ea81006548 Mika Westerberg 2017-10-13 2959 &bus->busn_res, max - start);
1c02ea81006548 Mika Westerberg 2017-10-13 2960 }
e16b46605960bd Keith Busch 2016-07-21 2961 }
e16b46605960bd Keith Busch 2016-07-21 2962
^1da177e4c3f41 Linus Torvalds 2005-04-16 2963 /*
^1da177e4c3f41 Linus Torvalds 2005-04-16 2964 * We've scanned the bus and so we know all about what's on
^1da177e4c3f41 Linus Torvalds 2005-04-16 2965 * the other side of any bridges that may be on this bus plus
^1da177e4c3f41 Linus Torvalds 2005-04-16 2966 * any devices.
^1da177e4c3f41 Linus Torvalds 2005-04-16 2967 *
^1da177e4c3f41 Linus Torvalds 2005-04-16 2968 * Return how far we've got finding sub-buses.
^1da177e4c3f41 Linus Torvalds 2005-04-16 2969 */
0207c356ef0e2b Bjorn Helgaas 2009-11-04 2970 dev_dbg(&bus->dev, "bus scan returning with max=%02x\n", max);
^1da177e4c3f41 Linus Torvalds 2005-04-16 2971 return max;
^1da177e4c3f41 Linus Torvalds 2005-04-16 2972 }
1c02ea81006548 Mika Westerberg 2017-10-13 2973
--
0-DAY CI Kernel Test Service
https://01.org/lkp
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH v2 2/4] PCI: Move jailhouse's isolated function handling to pci_scan_slot()
2022-04-12 14:30 [PATCH v2 0/4] PCI: Rework pci_scan_slot() and isolated PCI functions Niklas Schnelle
@ 2022-04-12 14:30 ` Niklas Schnelle
2022-04-12 16:28 ` kernel test robot
2022-04-12 19:43 ` kernel test robot
0 siblings, 2 replies; 6+ messages in thread
From: Niklas Schnelle @ 2022-04-12 14:30 UTC (permalink / raw)
To: Bjorn Helgaas, Jan Kiszka, Matthew Rosato, Pierre Morel
Cc: linux-s390, linux-pci
The special case of the jailhouse hypervisor passing through individual
PCI functions handles scanning for PCI functions even if function 0 does
not exist. Currently this is done with an extra loop duplicating the one
in pci_scan_slot(). By incorporating the check for jailhouse_paravirt()
into next_fn() we can instead do this as part of the normal
pci_scan_slot(). The only functional change is that we now call
pcie_aspm_init_link_state() for these functions but this already
happened if function 0 was passed through and should not be a problem.
Link: https://lore.kernel.org/linux-pci/20220408224514.GA353445@bhelgaas/
Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
---
drivers/pci/probe.c | 25 ++++++-------------------
1 file changed, 6 insertions(+), 19 deletions(-)
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 389aa1f9cb2c..8100e044dfc5 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -2602,10 +2602,11 @@ static int next_fn(struct pci_bus *bus, struct pci_dev *dev, int fn)
if (dev && !dev->multifunction)
return -ENODEV;
/*
- * A function 0 is required but multifunction devices may
- * be non-contiguous so dev can be NULL otherwise.
+ * Usually a function 0 is required but the jailhouse hypervisor may
+ * pass individual functions. For non-contiguous multifunction devices
+ * some functions may also be missing.
*/
- if (!fn && !dev)
+ if (!fn && !dev && !jailhouse_paravirt())
return -ENODEV;
return (fn <= 6) ? fn + 1 : -ENODEV;
}
@@ -2855,30 +2856,16 @@ static unsigned int pci_scan_child_bus_extend(struct pci_bus *bus,
{
unsigned int used_buses, normal_bridges = 0, hotplug_bridges = 0;
unsigned int start = bus->busn_res.start;
- unsigned int devfn, fn, cmax, max = start;
+ unsigned int devfn, cmax, max = start;
struct pci_dev *dev;
int nr_devs;
dev_dbg(&bus->dev, "scanning bus\n");
/* Go find them, Rover! */
- for (devfn = 0; devfn < 256; devfn += 8) {
+ for (devfn = 0; devfn < 256; devfn += 8)
nr_devs = pci_scan_slot(bus, devfn);
- /*
- * The Jailhouse hypervisor may pass individual functions of a
- * multi-function device to a guest without passing function 0.
- * Look for them as well.
- */
- if (jailhouse_paravirt() && nr_devs == 0) {
- for (fn = 1; fn < 8; fn++) {
- dev = pci_scan_single_device(bus, devfn + fn);
- if (dev)
- dev->multifunction = 1;
- }
- }
- }
-
/* Reserve buses for SR-IOV capability */
used_buses = pci_iov_bus_range(bus);
max += used_buses;
--
2.32.0
^ permalink raw reply related [flat|nested] 6+ messages in thread
end of thread, other threads:[~2022-04-13 22:12 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-04-13 22:12 [PATCH v2 2/4] PCI: Move jailhouse's isolated function handling to pci_scan_slot() kernel test robot
-- strict thread matches above, loose matches on Subject: below --
2022-04-12 14:30 [PATCH v2 0/4] PCI: Rework pci_scan_slot() and isolated PCI functions Niklas Schnelle
2022-04-12 14:30 ` [PATCH v2 2/4] PCI: Move jailhouse's isolated function handling to pci_scan_slot() Niklas Schnelle
2022-04-12 16:28 ` kernel test robot
2022-04-13 7:55 ` Niklas Schnelle
2022-04-13 7:55 ` Niklas Schnelle
2022-04-12 19:43 ` kernel test robot
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.