'vmap allocation for size %lu failed: use vmalloc=<size> to increase size'
The above warning is seen in the kernel functionality for allocation of the 
restricted virtual memory range till exhaustion.

This message is misleading because 'vmalloc=' is supported on arm32, x86 
platforms and is not a valid kernel parameter on a number of other platforms 
(in particular its not supported on arm64, alpha, loongarch, arc, csky, 
hexagon, microblaze, mips, nios2, openrisc, parisc, m64k, powerpc, riscv, sh, 
um, xtensa, s390, sparc). With the update, the output gets modified to include 
the function parameters along with the start and end of the virtual memory 
range allowed.

The warning message after fix on kernel version 6.10.0-rc1+:

vmalloc_node_range for size 33619968 failed: Address range restricted between 
0xffff800082640000 - 0xffff800084650000

Backtrace with the misleading error message:

        vmap allocation for size 33619968 failed: use vmalloc=<size> to 
increase size
        insmod: vmalloc error: size 33554432, vm_struct allocation failed, 
mode:0xcc0(GFP_KERNEL), nodemask=(null),cpuset=/,mems_allowed=0
        CPU: 46 PID: 1977 Comm: insmod Tainted: G            E      6.10.0-rc1+ 
#79
        Hardware name: INGRASYS Yushan Server iSystem TEMP-S000141176+10/Yushan 
Motherboard, BIOS 2.10.20230517 (SCP: xxx) yyyy/mm/dd
        Call trace:
                dump_backtrace+0xa0/0x128
                show_stack+0x20/0x38
                dump_stack_lvl+0x78/0x90
                dump_stack+0x18/0x28
                warn_alloc+0x12c/0x1b8
                __vmalloc_node_range_noprof+0x28c/0x7e0
                custom_init+0xb4/0xfff8 [test_driver]
                do_one_initcall+0x60/0x290
                do_init_module+0x68/0x250
                load_module+0x236c/0x2428
                init_module_from_file+0x8c/0xd8
                __arm64_sys_finit_module+0x1b4/0x388
                invoke_syscall+0x78/0x108
                el0_svc_common.constprop.0+0x48/0xf0
                do_el0_svc+0x24/0x38
                el0_svc+0x3c/0x130
                el0t_64_sync_handler+0x100/0x130
                el0t_64_sync+0x190/0x198

Reviewed-by: Christoph Lameter (Ampere) <[email protected]>
Signed-off-by: Shubhang Kaushik <[email protected]>
---
 Documentation/admin-guide/kernel-parameters.txt | 9 ++++++---
 mm/vmalloc.c                                    | 4 ++--
 2 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/Documentation/admin-guide/kernel-parameters.txt 
b/Documentation/admin-guide/kernel-parameters.txt
index b600df82669d..9b8f8ab90284 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -7245,9 +7245,12 @@
 
        vmalloc=nn[KMG] [KNL,BOOT,EARLY] Forces the vmalloc area to have an
                        exact size of <nn>. This can be used to increase
-                       the minimum size (128MB on x86). It can also be
-                       used to decrease the size and leave more room
-                       for directly mapped kernel RAM.
+                       the minimum size (128MB on x86, arm32 platforms).
+                       It can also be used to decrease the size and leave more 
room
+                       for directly mapped kernel RAM. Note that this 
parameter does
+                       not exist on many other platforms (including arm64, 
alpha,
+                       loongarch, arc, csky, hexagon, microblaze, mips, nios2, 
openrisc,
+                       parisc, m64k, powerpc, riscv, sh, um, xtensa, s390, 
sparc).
 
        vmcp_cma=nn[MG] [KNL,S390,EARLY]
                        Sets the memory size reserved for contiguous memory
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 5d3aa2dc88a8..75ad551e90ba 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -2055,8 +2055,8 @@ static struct vmap_area *alloc_vmap_area(unsigned long 
size,
        }
 
        if (!(gfp_mask & __GFP_NOWARN) && printk_ratelimit())
-               pr_warn("vmap allocation for size %lu failed: use 
vmalloc=<size> to increase size\n",
-                       size);
+               pr_warn("vmalloc_node_range for size %lu failed: Address range 
restricted to %#lx - %#lx\n",
+                               size, addr, addr+size);
 
        kmem_cache_free(vmap_area_cachep, va);
        return ERR_PTR(-EBUSY);
-- 
2.39.2

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