Why the memory cannot be written?

[bayesian]

I have already implemented physic allocation and paging. But I found otherwise I got the right virtual address of the memory, I cannot write the memory.
It's my testing code, physic_alloc will return physic address of page(s) witch can fit request size.
And interrupt is active, paging fault handler also is setted.

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	int* arr = (int*) ((uint32_t)physic_alloc(45*sizeof(int)) + PAGE_OFFSET);
	for(int i = 0; i<12; ++i) {
		arr[i] = i;
	}

	for(int i = 0; i<12; ++i) {
		printf("%d\n", arr[i]);
	}
	arr[2] = 4;

The testing outputs no error or exception, but

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0
0
0
... ('0' * 12)

In another test, I try to set value of members of a struct, but there is no effect.
The target address, 0xe00d9000, its page directory entry is

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pdg_k[0x380] = 0x18e003

page entry is

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tables[0x80][0xd9] = 0x200d9003

So the paging target is right, and RW bit is true, why the page cannot be wrote?

It's my code to enable paging. 0x00000000 -> 0xC0000000

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uint32_t cr0;
asm volatile ("mov %%cr0, %0" : "=r" (cr0));
cr0 |= 0x80000000;
asm volatile ("mov %0, %%cr0" : : "r" (cr0));

[Octocontrabass]

What does the firmware memory map say?