The patch titled Subject: mm/zsmalloc: include sparsemem.h for MAX_PHYSMEM_BITS has been added to the -mm tree. Its filename is mm-zsmalloc-include-sparsememh-for-max_physmem_bits.patch This patch should soon appear at https://ozlabs.org/~akpm/mmots/broken-out/mm-zsmalloc-include-sparsememh-for-max_physmem_bits.patch and later at https://ozlabs.org/~akpm/mmotm/broken-out/mm-zsmalloc-include-sparsememh-for-max_physmem_bits.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Stefan Agner <stefan@xxxxxxxx> Subject: mm/zsmalloc: include sparsemem.h for MAX_PHYSMEM_BITS Most architectures define MAX_PHYSMEM_BITS in asm/sparsemem.h and don't include it in asm/pgtable.h. Include asm/sparsemem.h directly to get the MAX_PHYSMEM_BITS define on all architectures. This fixes a crash when accessing zram on 32-bit ARM platform with LPAE and more than 4GB of memory: Unable to handle kernel NULL pointer dereference at virtual address 00000000 pgd = a27bd01c [00000000] *pgd=236a0003, *pmd=1ffa64003 Internal error: Oops: 207 [#1] SMP ARM Modules linked in: mdio_bcm_unimac(+) brcmfmac cfg80211 brcmutil raspberrypi_hwmon hci_uart crc32_arm_ce bcm2711_thermal phy_generic genet CPU: 0 PID: 123 Comm: mkfs.ext4 Not tainted 5.9.6 #1 Hardware name: BCM2711 PC is at zs_map_object+0x94/0x338 LR is at zram_bvec_rw.constprop.0+0x330/0xa64 pc : [<c0602b38>] lr : [<c0bda6a0>] psr: 60000013 sp : e376bbe0 ip : 00000000 fp : c1e2921c r10: 00000002 r9 : c1dda730 r8 : 00000000 r7 : e8ff7a00 r6 : 00000000 r5 : 02f9ffa0 r4 : e3710000 r3 : 000fdffe r2 : c1e0ce80 r1 : ebf979a0 r0 : 00000000 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5383d Table: 235c2a80 DAC: fffffffd Process mkfs.ext4 (pid: 123, stack limit = 0x495a22e6) Stack: (0xe376bbe0 to 0xe376c000) ... [<c0602b38>] (zs_map_object) from [<c0bda6a0>] (zram_bvec_rw.constprop.0+0x330/0xa64) [<c0bda6a0>] (zram_bvec_rw.constprop.0) from [<c0bdaf78>] (zram_submit_bio+0x1a4/0x40c) [<c0bdaf78>] (zram_submit_bio) from [<c085806c>] (submit_bio_noacct+0xd0/0x3c8) [<c085806c>] (submit_bio_noacct) from [<c08583b0>] (submit_bio+0x4c/0x190) [<c08583b0>] (submit_bio) from [<c06496b4>] (submit_bh_wbc+0x188/0x1b8) [<c06496b4>] (submit_bh_wbc) from [<c064ce98>] (__block_write_full_page+0x340/0x5e4) [<c064ce98>] (__block_write_full_page) from [<c064d3ec>] (block_write_full_page+0x128/0x170) [<c064d3ec>] (block_write_full_page) from [<c0591ae8>] (__writepage+0x14/0x68) [<c0591ae8>] (__writepage) from [<c0593efc>] (write_cache_pages+0x1bc/0x494) [<c0593efc>] (write_cache_pages) from [<c059422c>] (generic_writepages+0x58/0x8c) [<c059422c>] (generic_writepages) from [<c0594c24>] (do_writepages+0x48/0xec) [<c0594c24>] (do_writepages) from [<c0589330>] (__filemap_fdatawrite_range+0xf0/0x128) [<c0589330>] (__filemap_fdatawrite_range) from [<c05894bc>] (file_write_and_wait_range+0x48/0x98) [<c05894bc>] (file_write_and_wait_range) from [<c064f3f8>] (blkdev_fsync+0x1c/0x44) [<c064f3f8>] (blkdev_fsync) from [<c064408c>] (do_fsync+0x3c/0x70) [<c064408c>] (do_fsync) from [<c0400374>] (__sys_trace_return+0x0/0x2c) Exception stack(0xe376bfa8 to 0xe376bff0) bfa0: 0003d2e0 b6f7b6f0 00000003 00046e40 00001000 00000000 bfc0: 0003d2e0 b6f7b6f0 00000000 00000076 00000000 00000000 befcbb20 befcbb28 bfe0: b6f4e060 befcbad8 b6f23e0c b6dc4a80 Code: e5927000 e0050391 e0871005 e5918018 (e5983000) Link: https://lkml.kernel.org/r/bdfa44bf1c570b05d6c70898e2bbb0acf234ecdf.1604762181.git.stefan@xxxxxxxx Fixes: 61989a80fb3a ("staging: zsmalloc: zsmalloc memory allocation library") Signed-off-by: Stefan Agner <stefan@xxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/zsmalloc.c | 1 + 1 file changed, 1 insertion(+) --- a/mm/zsmalloc.c~mm-zsmalloc-include-sparsememh-for-max_physmem_bits +++ a/mm/zsmalloc.c @@ -40,6 +40,7 @@ #include <linux/string.h> #include <linux/slab.h> #include <linux/pgtable.h> +#include <asm/sparsemem.h> #include <asm/tlbflush.h> #include <linux/cpumask.h> #include <linux/cpu.h> _ Patches currently in -mm which might be from stefan@xxxxxxxx are mm-zsmalloc-include-sparsememh-for-max_physmem_bits.patch