RE: [kbuild-all] Re: [PATCH v4 4/7] iommu/vt-d: Handle non-page aligned address

Li, Philip
2020-07-09T01:11:08Z

> Subject: [kbuild-all] Re: [PATCH v4 4/7] iommu/vt-d: Handle non-page aligned
> address
>
> Hi Jacob,
>
> Thank you for the patch! Perhaps something to improve:
>
> [auto build test WARNING on iommu/next]
> [also build test WARNING on linux/master linus/master v5.8-rc4 next-20200707]
> [If your patch is applied to the wrong git tree, kindly drop us a note.
> And when submitting patch, we suggest to use as documented in
> https://git-scm.com/docs/git-format-patch]
>
> url: https://github.com/0day-ci/linux/commits/Jacob-Pan/iommu-vt-d-Misc-
> tweaks-and-fixes-for-vSVA/20200707-081026
> base: https://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu.git next
> config: x86_64-randconfig-m031-20200707 (attached as .config)
> compiler: gcc-9 (Debian 9.3.0-14) 9.3.0
>
> 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 >>):
Kindly ignore this, which is related to [-Wtype-limits], and is under
discussion to move such warning from W=1 to W=2 as it may not
suitable to fix which can hurt code readability.

Refer to https://lore.kernel.org/lkml/CAHk-=wiKCXEWKJ9dWUimGbrVRo_N2RosESUw8E7m9AEtyZcu=w@mail.gmail.com/
for the discussion.

>
> In file included from include/linux/string.h:6,
> from include/linux/uuid.h:12,
> from include/linux/mod_devicetable.h:13,
> from include/linux/pci.h:27,
> from drivers/iommu/intel/dmar.c:19:
> drivers/iommu/intel/dmar.c: In function 'qi_flush_dev_iotlb_pasid':
> include/linux/bits.h:26:28: warning: comparison of unsigned expression < 0 is
> always false [-Wtype-limits]
> 26 | __builtin_constant_p((l) > (h)), (l) > (h), 0)))
> | ^
> include/linux/compiler.h:58:52: note: in definition of macro '__trace_if_var'
> 58 | #define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) :
> __trace_if_value(cond))
> | ^~~~
> >> drivers/iommu/intel/dmar.c:1459:2: note: in expansion of macro 'if'
> 1459 | if (addr & GENMASK_ULL(size_order + VTD_PAGE_SHIFT, 0))
> | ^~
> include/linux/bits.h:25:3: note: in expansion of macro 'BUILD_BUG_ON_ZERO'
> 25 | (BUILD_BUG_ON_ZERO(__builtin_choose_expr( \
> | ^~~~~~~~~~~~~~~~~
> include/linux/bits.h:45:3: note: in expansion of macro
> 'GENMASK_INPUT_CHECK'
> 45 | (GENMASK_INPUT_CHECK(h, l) + __GENMASK_ULL(h, l))
> | ^~~~~~~~~~~~~~~~~~~
> drivers/iommu/intel/dmar.c:1459:13: note: in expansion of macro
> 'GENMASK_ULL'
> 1459 | if (addr & GENMASK_ULL(size_order + VTD_PAGE_SHIFT, 0))
> | ^~~~~~~~~~~
> include/linux/bits.h:26:40: warning: comparison of unsigned expression < 0 is
> always false [-Wtype-limits]
> 26 | __builtin_constant_p((l) > (h)), (l) > (h), 0)))
> | ^
> include/linux/compiler.h:58:52: note: in definition of macro '__trace_if_var'
> 58 | #define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) :
> __trace_if_value(cond))
> | ^~~~
> >> drivers/iommu/intel/dmar.c:1459:2: note: in expansion of macro 'if'
> 1459 | if (addr & GENMASK_ULL(size_order + VTD_PAGE_SHIFT, 0))
> | ^~
> include/linux/bits.h:25:3: note: in expansion of macro 'BUILD_BUG_ON_ZERO'
> 25 | (BUILD_BUG_ON_ZERO(__builtin_choose_expr( \
> | ^~~~~~~~~~~~~~~~~
> include/linux/bits.h:45:3: note: in expansion of macro
> 'GENMASK_INPUT_CHECK'
> 45 | (GENMASK_INPUT_CHECK(h, l) + __GENMASK_ULL(h, l))
> | ^~~~~~~~~~~~~~~~~~~
> drivers/iommu/intel/dmar.c:1459:13: note: in expansion of macro
> 'GENMASK_ULL'
> 1459 | if (addr & GENMASK_ULL(size_order + VTD_PAGE_SHIFT, 0))
> | ^~~~~~~~~~~
> include/linux/bits.h:26:28: warning: comparison of unsigned expression < 0 is
> always false [-Wtype-limits]
> 26 | __builtin_constant_p((l) > (h)), (l) > (h), 0)))
> | ^
> include/linux/compiler.h:58:61: note: in definition of macro '__trace_if_var'
> 58 | #define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) :
> __trace_if_value(cond))
> | ^~~~
> >> drivers/iommu/intel/dmar.c:1459:2: note: in expansion of macro 'if'
> 1459 | if (addr & GENMASK_ULL(size_order + VTD_PAGE_SHIFT, 0))
> | ^~
> include/linux/bits.h:25:3: note: in expansion of macro 'BUILD_BUG_ON_ZERO'
> 25 | (BUILD_BUG_ON_ZERO(__builtin_choose_expr( \
> | ^~~~~~~~~~~~~~~~~
> include/linux/bits.h:45:3: note: in expansion of macro
> 'GENMASK_INPUT_CHECK'
> 45 | (GENMASK_INPUT_CHECK(h, l) + __GENMASK_ULL(h, l))
> | ^~~~~~~~~~~~~~~~~~~
> drivers/iommu/intel/dmar.c:1459:13: note: in expansion of macro
> 'GENMASK_ULL'
> 1459 | if (addr & GENMASK_ULL(size_order + VTD_PAGE_SHIFT, 0))
> | ^~~~~~~~~~~
> include/linux/bits.h:26:40: warning: comparison of unsigned expression < 0 is
> always false [-Wtype-limits]
> 26 | __builtin_constant_p((l) > (h)), (l) > (h), 0)))
> | ^
> include/linux/compiler.h:58:61: note: in definition of macro '__trace_if_var'
> 58 | #define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) :
> __trace_if_value(cond))
> | ^~~~
> >> drivers/iommu/intel/dmar.c:1459:2: note: in expansion of macro 'if'
> 1459 | if (addr & GENMASK_ULL(size_order + VTD_PAGE_SHIFT, 0))
> | ^~
> include/linux/bits.h:25:3: note: in expansion of macro 'BUILD_BUG_ON_ZERO'
> 25 | (BUILD_BUG_ON_ZERO(__builtin_choose_expr( \
> | ^~~~~~~~~~~~~~~~~
> include/linux/bits.h:45:3: note: in expansion of macro
> 'GENMASK_INPUT_CHECK'
> 45 | (GENMASK_INPUT_CHECK(h, l) + __GENMASK_ULL(h, l))
> | ^~~~~~~~~~~~~~~~~~~
> drivers/iommu/intel/dmar.c:1459:13: note: in expansion of macro
> 'GENMASK_ULL'
> 1459 | if (addr & GENMASK_ULL(size_order + VTD_PAGE_SHIFT, 0))
> | ^~~~~~~~~~~
> include/linux/bits.h:26:28: warning: comparison of unsigned expression < 0 is
> always false [-Wtype-limits]
> 26 | __builtin_constant_p((l) > (h)), (l) > (h), 0)))
> | ^
> include/linux/compiler.h:69:3: note: in definition of macro '__trace_if_value'
> 69 | (cond) ? \
> | ^~~~
> include/linux/compiler.h:56:28: note: in expansion of macro '__trace_if_var'
> 56 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
> | ^~~~~~~~~~~~~~
> >> drivers/iommu/intel/dmar.c:1459:2: note: in expansion of macro 'if'
> 1459 | if (addr & GENMASK_ULL(size_order + VTD_PAGE_SHIFT, 0))
> | ^~
> include/linux/bits.h:25:3: note: in expansion of macro 'BUILD_BUG_ON_ZERO'
> 25 | (BUILD_BUG_ON_ZERO(__builtin_choose_expr( \
> | ^~~~~~~~~~~~~~~~~
> include/linux/bits.h:45:3: note: in expansion of macro
> 'GENMASK_INPUT_CHECK'
> 45 | (GENMASK_INPUT_CHECK(h, l) + __GENMASK_ULL(h, l))
> | ^~~~~~~~~~~~~~~~~~~
> drivers/iommu/intel/dmar.c:1459:13: note: in expansion of macro
> 'GENMASK_ULL'
> 1459 | if (addr & GENMASK_ULL(size_order + VTD_PAGE_SHIFT, 0))
> | ^~~~~~~~~~~
> include/linux/bits.h:26:40: warning: comparison of unsigned expression < 0 is
> always false [-Wtype-limits]
> 26 | __builtin_constant_p((l) > (h)), (l) > (h), 0)))
> | ^
> include/linux/compiler.h:69:3: note: in definition of macro '__trace_if_value'
> 69 | (cond) ? \
> | ^~~~
> include/linux/compiler.h:56:28: note: in expansion of macro '__trace_if_var'
> 56 | #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) )
> | ^~~~~~~~~~~~~~
> >> drivers/iommu/intel/dmar.c:1459:2: note: in expansion of macro 'if'
> 1459 | if (addr & GENMASK_ULL(size_order + VTD_PAGE_SHIFT, 0))
> | ^~
> include/linux/bits.h:25:3: note: in expansion of macro 'BUILD_BUG_ON_ZERO'
> 25 | (BUILD_BUG_ON_ZERO(__builtin_choose_expr( \
> | ^~~~~~~~~~~~~~~~~
> include/linux/bits.h:45:3: note: in expansion of macro
> 'GENMASK_INPUT_CHECK'
> 45 | (GENMASK_INPUT_CHECK(h, l) + __GENMASK_ULL(h, l))
> | ^~~~~~~~~~~~~~~~~~~
> drivers/iommu/intel/dmar.c:1459:13: note: in expansion of macro
> 'GENMASK_ULL'
> 1459 | if (addr & GENMASK_ULL(size_order + VTD_PAGE_SHIFT, 0))
> | ^~~~~~~~~~~
>
> vim +/if +1459 drivers/iommu/intel/dmar.c
>
> 1438
> 1439 /* PASID-based device IOTLB Invalidate */
> 1440 void qi_flush_dev_iotlb_pasid(struct intel_iommu *iommu, u16 sid, u16
> pfsid,
> 1441 u32 pasid, u16 qdep, u64 addr, unsigned int
> size_order)
> 1442 {
> 1443 unsigned long mask = 1UL << (VTD_PAGE_SHIFT + size_order -
> 1);
> 1444 struct qi_desc desc = {.qw1 = 0, .qw2 = 0, .qw3 = 0};
> 1445
> 1446 desc.qw0 = QI_DEV_EIOTLB_PASID(pasid) |
> QI_DEV_EIOTLB_SID(sid) |
> 1447 QI_DEV_EIOTLB_QDEP(qdep) | QI_DEIOTLB_TYPE |
> 1448 QI_DEV_IOTLB_PFSID(pfsid);
> 1449
> 1450 /*
> 1451 * If S bit is 0, we only flush a single page. If S bit is set,
> 1452 * The least significant zero bit indicates the invalidation address
> 1453 * range. VT-d spec 6.5.2.6.
> 1454 * e.g. address bit 12[0] indicates 8KB, 13[0] indicates 16KB.
> 1455 * size order = 0 is PAGE_SIZE 4KB
> 1456 * Max Invs Pending (MIP) is set to 0 for now until we have DIT in
> 1457 * ECAP.
> 1458 */
> > 1459 if (addr & GENMASK_ULL(size_order + VTD_PAGE_SHIFT, 0))
> 1460 pr_warn_ratelimited("Invalidate non-aligned address %llx,
> order %d\n", addr, size_order);
> 1461
> 1462 /* Take page address */
> 1463 desc.qw1 = QI_DEV_EIOTLB_ADDR(addr);
> 1464
> 1465 if (size_order) {
> 1466 /*
> 1467 * Existing 0s in address below size_order may be the
> least
> 1468 * significant bit, we must set them to 1s to avoid having
> 1469 * smaller size than desired.
> 1470 */
> 1471 desc.qw1 |= GENMASK_ULL(size_order +
> VTD_PAGE_SHIFT,
> 1472 VTD_PAGE_SHIFT);
> 1473 /* Clear size_order bit to indicate size */
> 1474 desc.qw1 &= ~mask;
> 1475 /* Set the S bit to indicate flushing more than 1 page */
> 1476 desc.qw1 |= QI_DEV_EIOTLB_SIZE;
> 1477 }
> 1478
> 1479 qi_submit_sync(iommu, &desc, 1, 0);
> 1480 }
> 1481
>
> ---
> 0-DAY CI Kernel Test Service, Intel Corporation
> https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org