# git rev-parse -q --verify 3c8ba0d61d04ced9f8d9ff93977995a9e4e96e91^{commit} 3c8ba0d61d04ced9f8d9ff93977995a9e4e96e91 already have revision, skipping fetch # git checkout -q -f -B kisskb 3c8ba0d61d04ced9f8d9ff93977995a9e4e96e91 # git clean -qxdf # < git log -1 # commit 3c8ba0d61d04ced9f8d9ff93977995a9e4e96e91 # Author: Kees Cook # Date: Fri Mar 30 18:52:36 2018 -0700 # # kernel.h: Retain constant expression output for max()/min() # # In the effort to remove all VLAs from the kernel[1], it is desirable to # build with -Wvla. However, this warning is overly pessimistic, in that # it is only happy with stack array sizes that are declared as constant # expressions, and not constant values. One case of this is the # evaluation of the max() macro which, due to its construction, ends up # converting constant expression arguments into a constant value result. # # All attempts to rewrite this macro with __builtin_constant_p() failed # with older compilers (e.g. gcc 4.4)[2]. However, Martin Uecker, # constructed[3] a mind-shattering solution that works everywhere. # Cthulhu fhtagn! # # This patch updates the min()/max() macros to evaluate to a constant # expression when called on constant expression arguments. This removes # several false-positive stack VLA warnings from an x86 allmodconfig build # when -Wvla is added: # # $ diff -u before.txt after.txt | grep ^- # -drivers/input/touchscreen/cyttsp4_core.c:871:2: warning: ISO C90 forbids variable length array ‘ids’ [-Wvla] # -fs/btrfs/tree-checker.c:344:4: warning: ISO C90 forbids variable length array ‘namebuf’ [-Wvla] # -lib/vsprintf.c:747:2: warning: ISO C90 forbids variable length array ‘sym’ [-Wvla] # -net/ipv4/proc.c:403:2: warning: ISO C90 forbids variable length array ‘buff’ [-Wvla] # -net/ipv6/proc.c:198:2: warning: ISO C90 forbids variable length array ‘buff’ [-Wvla] # -net/ipv6/proc.c:218:2: warning: ISO C90 forbids variable length array ‘buff64’ [-Wvla] # # This also updates two cases where different enums were being compared # and explicitly casts them to int (which matches the old side-effect of # the single-evaluation code): one in tpm/tpm_tis_core.h, and one in # drm/drm_color_mgmt.c. # # [1] https://lkml.org/lkml/2018/3/7/621 # [2] https://lkml.org/lkml/2018/3/10/170 # [3] https://lkml.org/lkml/2018/3/20/845 # # Co-Developed-by: Linus Torvalds # Co-Developed-by: Martin Uecker # Signed-off-by: Kees Cook # Acked-by: Ingo Molnar # Acked-by: Miguel Ojeda # Signed-off-by: Linus Torvalds # < /opt/cross/kisskb/gcc-4.6.3-nolibc/i386-linux/bin/i386-linux-gcc --version # < git log --format=%s --max-count=1 3c8ba0d61d04ced9f8d9ff93977995a9e4e96e91 # < make -s -j 10 ARCH=i386 O=/kisskb/build/linus_i386-allmodconfig_i386 CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/i386-linux/bin/i386-linux- allmodconfig WARNING: unmet direct dependencies detected for GPIO_CS5535 Depends on [m]: GPIOLIB [=y] && (X86 [=y] || MIPS || COMPILE_TEST [=y]) && MFD_CS5535 [=m] Selected by [y]: - OLPC_XO1_SCI [=y] && X86_32 [=y] && OLPC [=y] && OLPC_XO1_PM [=y] && INPUT [=y]=y # Added to kconfig CONFIG_BUILD_DOCSRC=n # Added to kconfig CONFIG_MODULE_SIG=n # Added to kconfig CONFIG_SAMPLES=n # yes \n | make -s -j 10 ARCH=i386 O=/kisskb/build/linus_i386-allmodconfig_i386 CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/i386-linux/bin/i386-linux- oldconfig yes: standard output: Broken pipe yes: write error # make -s -j 10 ARCH=i386 O=/kisskb/build/linus_i386-allmodconfig_i386 CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/i386-linux/bin/i386-linux- WARNING: unmet direct dependencies detected for GPIO_CS5535 Depends on [m]: GPIOLIB [=y] && (X86 [=y] || MIPS || COMPILE_TEST [=y]) && MFD_CS5535 [=m] Selected by [y]: - OLPC_XO1_SCI [=y] && X86_32 [=y] && OLPC [=y] && OLPC_XO1_PM [=y] && INPUT [=y]=y WARNING: unmet direct dependencies detected for GPIO_CS5535 Depends on [m]: GPIOLIB [=y] && (X86 [=y] || MIPS || COMPILE_TEST [=y]) && MFD_CS5535 [=m] Selected by [y]: - OLPC_XO1_SCI [=y] && X86_32 [=y] && OLPC [=y] && OLPC_XO1_PM [=y] && INPUT [=y]=y CONFIG_CC_STACKPROTECTOR_AUTO: -fstack-protector available but compiler is broken: disabling /kisskb/src/arch/x86/kernel/e820.c: In function 'e820__setup_pci_gap': /kisskb/src/arch/x86/kernel/e820.c:652:2: warning: 'gapstart' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/arch/x86/kernel/hw_breakpoint.c: In function 'arch_validate_hwbkpt_settings': /kisskb/src/arch/x86/kernel/hw_breakpoint.c:361:20: warning: 'align' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/arch/x86/kvm/svm.c: In function 'sev_dbg_crypt.isra.56': /kisskb/src/arch/x86/kvm/svm.c:6563:6: warning: 'ret' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/arch/x86/kvm/svm.c: In function 'sev_launch_update_data.isra.50': /kisskb/src/arch/x86/kvm/svm.c:6214:9: warning: 'ret' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/arch/x86/kernel/apic/io_apic.c: In function 'mp_map_pin_to_irq': /kisskb/src/arch/x86/kernel/apic/io_apic.c:1033:6: warning: 'irq' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/kernel/cgroup/cgroup-v1.c: In function 'cgroup1_mount': /kisskb/src/kernel/cgroup/cgroup-v1.c:1268:20: warning: 'root' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/mm/hugetlb.c: In function 'alloc_pool_huge_page': /kisskb/src/mm/hugetlb.c:1440:5: warning: 'page' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/kernel/printk/printk.c: In function 'devkmsg_sysctl_set_loglvl': /kisskb/src/kernel/printk/printk.c:183:16: warning: 'old' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/sound/hda/hdac_regmap.c: In function 'hda_reg_write': /kisskb/src/sound/hda/hdac_regmap.c:282:16: warning: 'err' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/fs/btrfs/ref-verify.c: In function 'process_extent_item.isra.2': /kisskb/src/fs/btrfs/ref-verify.c:516:2: warning: 'ret' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/fs/btrfs/ref-verify.c: In function 'process_leaf.isra.3': /kisskb/src/fs/btrfs/ref-verify.c:568:2: warning: 'ret' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/fs/f2fs/file.c: In function 'f2fs_precache_extents': /kisskb/src/fs/f2fs/file.c:2786:6: warning: 'err' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/base/regmap/regmap.c: In function 'regmap_raw_read': /kisskb/src/drivers/base/regmap/regmap.c:2497:6: warning: 'ret' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/base/regmap/regmap.c: In function '_regmap_raw_write': /kisskb/src/drivers/base/regmap/regmap.c:1819:6: warning: 'ret' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/lib/raid6/recov_avx512.c:387:2: warning: #warning "your version of binutils lacks AVX512 support" [-Wcpp] /kisskb/src/sound/soc/codecs/arizona.c: In function 'arizona_hw_params': /kisskb/src/sound/soc/codecs/arizona.c:1893:3: warning: 'aif_rx_state' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/sound/soc/codecs/arizona.c:1890:3: warning: 'aif_tx_state' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/sound/soc/codecs/da7219-aad.c: In function 'da7219_aad_hptest_work': /kisskb/src/sound/soc/codecs/da7219-aad.c:318:17: warning: 'pll_ctrl' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/net/bridge/br_netlink.c: In function 'br_process_vlan_info': /kisskb/src/net/bridge/br_netlink.c:577:10: warning: 'err' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/sound/soc/codecs/rt5665.c: In function 'rt5665_i2s_pin_event': /kisskb/src/sound/soc/codecs/rt5665.c:2666:33: warning: 'val2' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/sound/soc/codecs/rt5665.c:2663:33: warning: 'val1' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/clk/renesas/clk-sh73a0.c: In function 'sh73a0_cpg_register_clock': /kisskb/src/drivers/clk/renesas/clk-sh73a0.c:155:3: warning: 'parent_name' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/fs/nfsd/nfs4xdr.c: In function 'nfsd4_encode_components_esc': /kisskb/src/fs/nfsd/nfs4xdr.c:2043:9: warning: 'str' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/fs/nfsd/nfs4xdr.c:2048:11: warning: 'end' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/dma-buf/reservation.c: In function 'reservation_object_add_shared_replace': /kisskb/src/drivers/dma-buf/reservation.c:207:2: warning: 'k' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/dma-buf/reservation.c:210:7: warning: 'i' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c: In function 'amdgpu_set_pp_od_clk_voltage': /kisskb/src/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c:414:5: warning: 'ret' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/net/mac80211/mlme.c: In function 'ieee80211_handle_pwr_constr.isra.13': /kisskb/src/net/mac80211/mlme.c:1352:3: warning: 'pwr_level_cisco' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/net/mac80211/mesh_pathtbl.c: In function 'mesh_path_add': /kisskb/src/net/mac80211/mesh_pathtbl.c:417:28: warning: 'new_mpath' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/infiniband/hw/cxgb4/device.c: In function 'wr_log_show': /kisskb/src/drivers/infiniband/hw/cxgb4/device.c:152:14: warning: 'prev_time' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/gpu/drm/amd/amdgpu/../display/dc/calcs/dce_calcs.c: In function 'calculate_bandwidth': /kisskb/src/drivers/gpu/drm/amd/amdgpu/../display/dc/calcs/dce_calcs.c:2017:1: warning: the frame size of 1032 bytes is larger than 1024 bytes [-Wframe-larger-than=] /kisskb/src/drivers/input/rmi4/rmi_f11.c: In function 'rmi_f11_finger_handler': /kisskb/src/drivers/input/rmi4/rmi_f11.c:631:3: warning: 'abs_fingers' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/iommu/io-pgtable-arm-v7s.c: In function '__arm_v7s_map': /kisskb/src/drivers/iommu/io-pgtable-arm-v7s.c:468:2: warning: 'cptep' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/gpu/drm/nouveau/nvkm/subdev/top/gk104.c: In function 'gk104_top_oneinit': /kisskb/src/drivers/gpu/drm/nouveau/nvkm/subdev/top/gk104.c:101:1: warning: 'inst' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/gpu/drm/nouveau/nvkm/subdev/top/gk104.c:101:1: warning: 'type' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/net/vmw_vsock/hyperv_transport.c: In function 'hvs_open_connection': /kisskb/src/net/vmw_vsock/hyperv_transport.c:399:24: warning: 'hvs_new' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/net/vmw_vsock/hyperv_transport.c:383:14: warning: 'hvs' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/net/vmw_vsock/hyperv_transport.c:202:20: warning: 'vnew' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/net/vmw_vsock/hyperv_transport.c:331:21: note: 'vnew' was declared here /kisskb/src/drivers/media/usb/dvb-usb/pctv452e.c: In function 'pctv452e_frontend_attach': /kisskb/src/drivers/media/usb/dvb-usb/pctv452e.c:922:2: warning: value computed is not used [-Wunused-value] /kisskb/src/drivers/net/wireless/broadcom/b43/phy_n.c: In function 'b43_nphy_rf_ctl_override_rev7': /kisskb/src/drivers/net/wireless/broadcom/b43/phy_n.c:202:21: warning: 'val_addr' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c: In function 'hclgevf_bind_ring_to_vector': /kisskb/src/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c:609:16: warning: 'type' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/net/tun.c: In function 'tun_get_user': /kisskb/src/drivers/net/tun.c:1820:30: warning: 'copylen' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/net/tun.c:1530:34: warning: 'linear' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/net/tun.c:1730:46: note: 'linear' was declared here /kisskb/src/drivers/net/ethernet/intel/ice/ice_main.c: In function 'ice_vsi_open': /kisskb/src/drivers/net/ethernet/intel/ice/ice_main.c:4983:5: warning: 'err' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/net/ethernet/intel/ice/ice_main.c:4987:5: warning: 'err' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/net/ethernet/mellanox/mlx5/core/fs_core.c: In function 'update_root_ft_create': /kisskb/src/drivers/net/ethernet/mellanox/mlx5/core/fs_core.c:872:5: warning: 'err' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c: In function 'rtl8723a_phy_lc_calibrate': /kisskb/src/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c:3481:23: warning: 'rf_amode' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/staging/fsl-dpaa2/ethsw/ethsw.c: In function 'port_vlans_add': /kisskb/src/drivers/staging/fsl-dpaa2/ethsw/ethsw.c:720:11: warning: 'err' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/staging/fsl-dpaa2/ethsw/ethsw.c: In function 'swdev_port_obj_del': /kisskb/src/drivers/staging/fsl-dpaa2/ethsw/ethsw.c:923:2: warning: 'err' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/video/fbdev/intelfb/intelfbhw.c: In function 'calc_pll_params': /kisskb/src/drivers/video/fbdev/intelfb/intelfbhw.c:1012:2: warning: 'm2' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/video/fbdev/intelfb/intelfbhw.c:1012:2: warning: 'm1' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/staging/lustre/lustre/ptlrpc/nrs.c: In function 'ptlrpc_nrs_policy_register.constprop.12': /kisskb/src/include/linux/string.h:266:29: warning: array subscript is above array bounds [-Warray-bounds] Completed OK # rm -rf /kisskb/build/linus_i386-allmodconfig_i386 # Build took: 0:14:00.911413