Re: [PATCH 2/2] KVMM: Memory and interface related changes

[kbuild test robot]

Hi Anastassios,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on v5.7-rc6]
[cannot apply to kvm/linux-next kvmarm/next tip/x86/core next-20200515]
[if your patch is applied to the wrong git tree, please drop us a note to help
improve the system. BTW, we also suggest to use '--base' option to specify the
base tree in git format-patch, please see https://stackoverflow.com/a/37406982]

url:    https://github.com/0day-ci/linux/commits/Anastassios-Nanos/Expose-KVM-API-to-Linux-Kernel/20200518-150402
base:    b9bbe6ed63b2b9f2c9ee5cbd0f2c946a2723f4ce
config: powerpc-defconfig (attached as .config)
compiler: powerpc64-linux-gcc (GCC) 9.3.0
reproduce:
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=powerpc 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kbuild test robot <lkp@xxxxxxxxx>

All errors (new ones prefixed by >>, old ones prefixed by <<):

arch/powerpc/kvm/../../../virt/kvm/kvm_main.c: In function 'hva_to_pfn_slow':
>> arch/powerpc/kvm/../../../virt/kvm/kvm_main.c:1837:4: error: 'npages_local' undeclared (first use in this function)
1837 |    npages_local = 1;
|    ^~~~~~~~~~~~
arch/powerpc/kvm/../../../virt/kvm/kvm_main.c:1837:4: note: each undeclared identifier is reported only once for each function it appears in

vim +/npages_local +1837 arch/powerpc/kvm/../../../virt/kvm/kvm_main.c

  1800	
  1801	/*
  1802	 * The slow path to get the pfn of the specified host virtual address,
  1803	 * 1 indicates success, -errno is returned if error is detected.
  1804	 */
  1805	static int hva_to_pfn_slow(unsigned long addr, bool *async, bool write_fault,
  1806				   bool *writable, kvm_pfn_t *pfn)
  1807	{
  1808		unsigned int flags = FOLL_HWPOISON;
  1809		struct page *page;
  1810		int npages = 0;
  1811	
  1812		might_sleep();
  1813	
  1814		if (writable)
  1815			*writable = write_fault;
  1816	
  1817		if (write_fault)
  1818			flags |= FOLL_WRITE;
  1819		if (async)
  1820			flags |= FOLL_NOWAIT;
  1821	
  1822		if (kvmm_valid_addr(addr)) {
  1823			npages = 1;
  1824			page = vmalloc_to_page((void *)addr);
  1825		} else {
  1826			npages = get_user_pages_unlocked(addr, 1, &page, flags);
  1827		}
  1828		if (npages != 1)
  1829			return npages;
  1830	
  1831		/* map read fault as writable if possible */
  1832		if (unlikely(!write_fault) && writable) {
  1833			struct page *wpage;
  1834			int lnpages = 0;
  1835	
  1836			if (kvmm_valid_addr(addr)) {
> 1837				npages_local = 1;
  1838				wpage = vmalloc_to_page((void *)addr);
  1839			} else {
  1840				lnpages = __get_user_pages_fast(addr, 1, 1, &wpage);
  1841			}
  1842	
  1843			if (lnpages == 1) {
  1844				*writable = true;
  1845				put_page(page);
  1846				page = wpage;
  1847			}
  1848		}
  1849		*pfn = page_to_pfn(page);
  1850		return npages;
  1851	}
  1852	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx

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